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Hi all .Questions from a newbie

lc7404

Well-Known Member
Messages
69
Location
ohio
Hi all. Just purchased a 07 H3 135k. Next weekend I be doing a tune up and changing all fluids. I will be using AC Delco plugs . i have been reading the post and trying to make a final decision on Airfilters also if I should grab a Volant? What oil would you recommend Royal Purple? Now the big question . I read about the dreaded radiator problem. Should I just go ahead and replace it now with a Cfs one ? Or separate inter cool system. Thank you for the replies and glad to be part of the hummer family
 

JPaul

Well-Known Member
Messages
2,400
Location
Way up north, UT
Genuine AC Delco air filter, they flow plenty, seal properly, and keep the dust out of the engine the best. Don't get anything from the parts stores, except maybe a Wix filter (I think Wix is the OEM supplier for AC Delco), if you look at the OEM filter vs a Fram or STP or anything like that, you'll see the material is lower quality on the aftermarket, as is the seal. I tried using a STP once, and it did not seal properly and let far too much dust past. Volant is just going to suck hot air from the engine bay in and doesn't filter as well. The factory airbox is already a true cold air intake, it draws air completely from outside the engine bay. If you really feel it's necessary to use a washable filter, I'd personally go with a dry filter like AEM or something. Or use a KN filter if you want. But despite everyone's claims I am extremely hesitant to accept that they filter anywhere close to the OEM filter. Dust and grit will wreck your top end in short order. What's more important, a few extra ponies at the top end, or an engine that will last as long as it ought to? That's the question you need to ask yourself. Filters can be had for $20 or so off Amazon.

For oil just use Mobil 1 full synth high mileage, Royal purple is probably great and all, but insanely expensive. Mobil filters are some of the best as well, don't bother with KN (rebadged and more expensive), or Fram (not up to the same quality standards), and the AC Delco filter you find these days is their economy version which isn't much better than a cheap Fram. Both can be had at Walmart for less than the auto parts stores.

With the radiator some have had success with the aluminum ones, others have developed pinhole leaks repeatedly. I'd suggest going with an OEM replacement instead to save yourself any headache. Replacing it now if it hasn't already been replaced would be a wise idea. Make sure to clean out the fins of the AC condenser to make sure it's not blocking airflow to the radiator. Junk and dust like to build up between the condenser and the radiator.
 
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lc7404

Well-Known Member
Messages
69
Location
ohio
Thank You. Would you suggest going with a added inter cooler? or just new factory setup
 

JPaul

Well-Known Member
Messages
2,400
Location
Way up north, UT
If you mean transmission cooler then yes, I would at a minimum add an inline cooler to the stock setup. I myself bypassed the stock cooler completely on my Alpha since it was leaking past the o-rings where the lines enter the cooler. It's too easy to overheat the transmissions on these rigs with the stock setup.

If you add a transmission cooler inline with the stock one then you can have the benefit of it warming up faster during the winter and keeping the temperature up where it should be, but still have the additional cooling necessary during the summer. When going with bypassing the stock cooler you might have to add in a thermal bypass to allow the transmission to warm up during the winter. All depends on how cold it gets. Where I am the winters can get fairly cold and last winter I was seeing my temps staying too low for too long, so this time around I'll be adding in a bypass to allow it to get up to 140 degrees or so which is a good temp for it to be at.
 

mdocod

Well-Known Member
Messages
61
Location
Colorado Springs, Colorado
I also recommend sticking with good quality "OEM style" (paper media) air filters. They provide the best filtration. I haven't compared "brands" on these yet (for the H3) so can't comment on which brand for the H3 is a good option but I've used purolator/wix/fram in the past on other vehicles without issues. I make a point to see which brand is building the best looking filter for the application and go with it. Yes, sometimes that is a FRAM, despite their bad reputation from a bygone era. (though these days, FRAM is building some of the finest oil and air filters available so take a closer look!). I like to look for more pleats, more structure/rigidity (cross members where required), thicker/better feeling seals, etc. This will vary from application to application. If you are trying to get more power out of the engine, go ahead and go with a K&N or similar reduced-filtration, high flow media solution.

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For diff fluids, any modern 75W90 GL-5 synthetic is going to be fine. If you intend to tow a lot or do a lot of hard wheeling, consider 75W140 synthetic instead. In either case, there is no meaningful difference between brands on the shelf of local stores, so just get what you can find cheap. Store brands are fine here. If you want to go for something "fancy," order some RedLine Heavy ShockProof. 75W-90 will be a bit better on fuel economy and getting power to the road, while 75W-140 will buy a bit more wear protection.

For transmission fluid assuming the automatic transmission, any Dex VI or Dex III conforming ATF should work fine. If you want to go a little fancy for not much more money, valvoline maxlife full syn ATF is good and cheap. If you want to go fancy, redline D4 or D6 are worth a look. IMO I'd go with D4 if you want a bit more protection (slightly higher viscosity), and D6 if you want to eek out fuel economy/power.

For T-case, calls for DEX III or DEX VI or a special GM part number depending on what year your manual was printed. There's a ton of debate about which fluid is correct for these but the debate is probably silly because the answer is that all the fluids specified for this transfer case are likely to work fine. Dex III, Dex VI, special GM part numbers used to obfuscate, whatever you want. If you want to truly "upgrade" from the specified fluid, I'd look seriously at Redline High-Temp ATF, which is thicker and better suited for the forces involved that far down the driveline IMO. I intend to switch to this sometime down the road to provide a bit of protection for the additional heat anticipated from adding skid plates. If you want to maximize fuel economy and power to the road, go with a Dex VI product. If you want to maximize gear/chain protection, consider the Redline High Temp ATF stuff.

As for the transmission, T-Case, and diffs, it's likely that none have had their fluids changed, so it may be wise to plan on using cheap fluid in there on a shorter interval as a sort of cleaning flush.

As for engine oil, any 5W-30, 0W-30, 0W-40 API SN or better will work fine. A 5w-40 HDEO is also an option. I personally prefer to use various HDEO synthetics in all my vehicle engines. Lately I pick up whatever ACEA A3/B4 0W-30 or 0W-40 I can get cheapest. Walmart sells several options meeting the A3/B4 spec in 5 qt jugs for the same price as other synthetics. If you're going to run synthetic anyway (which most people do these days anyway), you may as well get one with better cold flow performance, better high HTHS viscosity, and better barrier lube add packs for the same price. This stuff is specified for use in turbo gas/diesel engines and most performance engines in european cars and sort of falls in-between what you'd get from a mainstream 5W-30 and a "heavy duty" HDEO like Rotella T6 5W-40. T6 is also great oil and would probably work great in the abused little i5, but T6 does run on the thicker end of a 40 weight, while most A3/B4 oils run on the thick end of a 30 weight or thin end of a 40 weight, while having better cold flow properties, so should strike a good balance for fuel economy and engine protection. That being said, my old isuzu always seemed to work best on T6. Ran quietest on it, seemed to have the best power on it, burned the least amount of oil on it and also didn't leak a drop when that was in the crank. All other oils seemed to leak and burn faster in that engine while running noisier. If you want to maximize engine protection, consider an HDEO like T6 or pretty much any 5W-40 synthetic meeting API CJ-4 / ACEA E9 performance category specification. If you want to maximize fuel economy and power, pick a 0W30 leaning to the thin end of 30 weight with a lower HTHS and non-HDEO characteristics, like Mobile 1 0W-30 Advanced Fuel Economy.

It would make sense to me, to be consistent with your approach to to bottom on choice of drivetrain fluids and air filtration. Pick if you want to lean on the side of caution, with thicker lubrication providing better boundary protection and reduced wear and more restrictive air and oil filters robbing power, or lean on the side of fuel economy and power output with high flow, non paper media air filters and thinner oils top to bottom.

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Don't forget the BRAKE FLUID!! this stuff should be changed every 2-4 years depending on climate regardless of mileage in most vehicles, and often goes neglected. A full brake fluid flush every few years will protect the metal guts of your brake system from rust damage. DOT 3/4 BRAKE fluid is hygroscopic!

I think valvoline DOT 3/4 fluid is a great value as it often goes on sale buy one get one at advance auto. With this fluid, the frequency that it is changed is more important than the brand name on the bottle by a long shot. It's all the same stuff. I advise DOT 4 for better high heat tolerance if you do a lot of hard braking or trailering. Otherwise DOT 3 is fine and is technically a bit less hygroscopic so shouldn't need to be changed as often so either way. I'm running 35's on mine so opted for DOT 4. Do not use DOT 5, it is not compatible with the system.

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Power Steering Fluid: GM, like almost all makes, likes to really try to obfuscate the crap out of fluids with "part numbers," to get people to buy their expensive bottle of cheap fluid. Based on the research I have done, the various part numbers you might run into in an H3 manual for power steering fluid all pretty much mean the same thing: "basic power steering fluid." Just pick up a bottle of power steering fluid. I like to make a point to suck the reservoir dry and refill with fresh fluid, then cycle the steering and repeat that a few times until it is running pretty clean looking, then redo that once every couple years.

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Oh yea... and one last thing. Don't forget the snake oil!!! lol.... In all honestly, you should never need to put an additive in any hole of any modern car, however, if you feel compelled to put more than just the usual stuff in a hole, here's some ideas that I happen to like:

For your engine, transmission, t-case, diffs, and power steering, Auto-RX is a gentle metal cleaner made from ester oils that you can leave in these systems long term to remove varnish and some other deposits in areas where there is high oil flow. I'm a believer in this product because I have seen it clean things up, reduce oil consumption and leaking on some engines and power steering systems. I also recall after having run it in a transmission that was opened up for a rebuild (not a required rebuild, just had it out anyway because I was having a married t-case upgraded to lower gearing). I asked the rebuilder about how the transmission looked and if it was worth opening up after the fact. He advised replacing the syncro friction cones and a couple forks that were wore out from age, but also commented on how unusually clean the inside of the unit was. Said he'd never seen a transmission at that age (~180K miles at the time) that looked so clean inside. He said the mating surfaces of the gears and all the shafts and everything were just unusually shiny/clean, like brand new metal with no varnish/deposits. The premise of the Auto-RX concept is that oil works best at protecting clean metal. Oil is actually repelled from varnished surfaces to an extent, preventing proper lubrication. The product actually has a neat story behind its invention (not car related, not "snake oil/as-seen-on-tv" origins), and a history of industrial use in commercial applications with proven results. I'll probably do a bit of ARX in hummer holes someday for good measure.

For top-end cleaning, (removing carbon deposits), water or methanol sucked down the intake do work. Products like Seafoam are also fun for this as they smoke out the whole village! (rolling seafoam?). The cloud of smoke is worth the $8 asking price when fire bans prevent the purchase of smoke bomb fireworks in the summer.

For fuel additives. I can't say with any certainty if a fuel additive has ever made any difference in any car I have owned over the years, but I tend to poor a bottle in the tank of each car at least once every year or 2 because it makes me feel good to poor a fancy bottle of weird looking elixir into the tank and then pretend I'm "fixing" my car as I drive it... lol. Gumout Regane, Chevron Techron, and Redline SI-1, are actually somewhat respected among people who give a darn about what snake oils are snake poop and what snake oils are actually capable of doing something.
 

Alpha X

Well-Known Member
Messages
409
Location
The Motor City
Genuine AC Delco air filter, they flow plenty, seal properly, and keep the dust out of the engine the best. Don't get anything from the parts stores, except maybe a Wix filter (I think Wix is the OEM supplier for AC Delco), if you look at hte OEM filter vs a Fram or STP or anything liek that, you'll see the material is lower quality on the aftermarket, as is the seal. I tried using a STP once, and it did not seal properly and let far too much dust past.

Good info, I was not aware of this. I think I have an STP in there now and will have to get an OE filter.
 

650Hawk

Well-Known Member
Messages
480
Location
SoCal
Lots of good info here, on everything from fluids to filters to additives. Thought I'd chime in with my experiences as well. I just recently did a fluids change; diffs and transfer case (trans fluid still to come); I used Royal Purple in the diffs, GM transfer case fluid in the TC. I always run Quaker State in my engines (other than my MH which gets Mobil1, and the Husqvarna which gets Rotella T6), and I've used Fram oil filters almost exclusively in all of my vehicles for pretty much the entire time I've been driving. Since I'm 56, that's been a while. Never had an issue with Fram oil filters, and still prefer the "textured" end so that they can be removed without a filter wrench.

K&N Air Filters. Nothing brings out more passionate discussions, on both sides of the aisle, than K&N air filters. I've seen all of the internet comparisons, read all of the arguments pro and con, and really don't want to start one here. I will, however, explain my reasons for using them, as well as my reasons for not recommending them, which are based on nearly 50 years of actual use. I have been riding and racing in the deserts of SoCal since I was 8 years old, including nearly a decade as a professional desert racer (M/C) back in the late 70's/early 80s. Since day 1, I have used K&N filters on every one of my offroad machines, and still do (I still ride ATVs, hard, in the sand dunes of Glamis). I also run K&N in my Hummer, my wife's 4x4 Tahoe, and my 8.1L Workhorse class A motorhome.

Because the K&N filter medium is 5X thicker than a typical dry paper filter, it has 5X more surface area (a paper filter must do it's job in 1/32", and K&N has 1/4" to do the same job). THAT is why it flows so much more air, NOT because it is not filtering as well (which is the often claimed argument against K&N). I currently have 3 full size vehicles and 5 offroad vehicles running K&N, everything from a built to the hilt 1985 ATC250R (that I purchased brand new) to a 2012 Husqvarna TE310; I have never, in 48 years, had any dirt or dust make it past a K&N filter on any of those (or previously owned) vehicles, and I regularly ride in dirty, dusty, demanding conditions.

That said, I do NOT recommend K&N air filters for most users. Why? Because "properly" cleaning and especially oiling a K&N is almost an art form, and is the #1 cause of the problems people have and/or claim about K&N filters. Not enough oil WILL allow dust to get past the medium, too much oil WILL foul MAF sensors on today's fuel injected engines. It's a balancing act, one that even my 25 year old son is still trying to perfect. I can do it in my sleep, but only because I HAVE been doing it for nearly 50 years. So while I will never use anything other than K&N for any vehicle that will see even occasional offroad use, I will also never recommend them to others (unless they want to hire me to clean and oil them as needed! :thumbs:). YMMV.
 
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lc7404

Well-Known Member
Messages
69
Location
ohio
Ty all for taking the time to chime in. A bit overwhelming but good knowledge. Any recommendations on a transmission cooler
 

alrock

El Diablo
Staff member
Messages
10,442
Location
Scottsdale
650, you nailed the primary reason that I dont use oiled filters. I suspect I will under oil or over oil the filter with poor results either way

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Mr_Rich

Well-Known Member
Messages
636
Location
High Desert & Santa Maria
Fram used to sell a paper filter for dusty conditions that would fit the air cleaner on my '89 Chev K1500 EC. It had a finer filter medium and I liked using them since I live in farming country. I think they stopped producing them many years ago since I could no longer find them. I think AC Delco filters are probably the best choice now. I use K&N oil filters exclusively on all my vehicles.
 

amrg

Well-Known Member
Messages
2,317
Location
Qatar
Ty all for taking the time to chime in. A bit overwhelming but good knowledge. Any recommendations on a transmission cooler
My recommendation:
https://www.amazon.com/dp/B00B0OYI9O/ref=cm_sw_r_cp_apa_NCokBbZDV5J9K


Just bypass the stock in rad cooler and go with this one. Too many stories here and other forums about the oil in the built in trans cooler mixing with coolant leading to catastrophic trans failure (if not caught early). At best you would be looking at a new rad, hoses and full engine and trans flush but the probable is a revuilt trans too.
If you live in a cold place, get the one with the thermal bypass. If you have 35s and tow regularly, get the bigger one for peace of mind.

There is a guy right now on another forum looking to rebuild his trans for this exact reason...





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Ordieh

Well-Known Member
Messages
152
Location
Georgetown texas
Hey 650HAWK,
I couldn't agree more about K&N! I'm 74 years old and my experience is exactly the same as yours. I have used them in everything from diesel RV's, motorcycles, farm tractors, to things like a built for racing Chevy 454 powered CJ5 and never seen any evidence of "dirt" entering. Can't imagine using anything else. And yes, I also agree that oiling is a skill.
Also, my buddy is a AH64D pilot and tells me that there are multiple K&N filters used in those desert flying machines.
 

f5moab

Mr. Beretta
Messages
1,986
Location
Hiding in a potato patch in Idaho
If you live in a desert area or like me surrounded by farms that are kicking up dust constantly; use a paper filter. If living in a big city with little comparable dust, oiled filter will be ok. But if you are allowing more air in, you are cutting down on filtration. And like someone already noted, if you oil it incorrectly with too much oil, expect some problems with a MAF and/or air intake sensor and dirtier throttle body; if not enough oil more dirt. But like I love to say...ain't my vehicle so run without a filter if you want.
 

650Hawk

Well-Known Member
Messages
480
Location
SoCal
If you live in a desert area or like me surrounded by farms that are kicking up dust constantly; use a paper filter. If living in a big city with little comparable dust, oiled filter will be ok. But if you are allowing more air in, you are cutting down on filtration. And like someone already noted, if you oil it incorrectly with too much oil, expect some problems with a MAF and/or air intake sensor and dirtier throttle body; if not enough oil more dirt. But like I love to say...ain't my vehicle so run without a filter if you want.
And there it is; the point I was trying to counter: More airflow does NOT mean less filtration. It is the 5X increase in actual "surface area" that allows more airflow without reduced filtration. Think of it this way: if you could modify your intake system to allow 5 paper filters, side by side, that would increase your airflow 5X WITHOUT decreasing the filtration ability, right? That is in effect what the K&N is doing.

Again, I have spent my life riding and racing in the SoCal deserts; I think that would qualify as "constant dust". There is a reason that nearly every vehicle racing in the Baja 1000 uses K&N filters. There is a reason that most duners in Glamis use K&N filters. There is a reason that I have NEVER seen any evidence of dirt or dust intrusion in any of my off-road vehicles in nearly 50 years (nor has Ordieh, above). IF they are oiled properly, nothing will out perform a K&N, both in airflow and filtration. But that is the key: IF they are PROPERLY oiled.
 
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Traxx

Well-Known Member
Messages
682
Location
PNW
I'd rather just throw a Delco filter in and spend my time doing something besides washing and oiling an air filter.
 

650Hawk

Well-Known Member
Messages
480
Location
SoCal
I'd rather just throw a Delco filter in and spend my time doing something besides washing and oiling an air filter.
Fair enough, but since my K&N will last 4-5X longer between cleanings than your paper filter replacement, how much time are you actually saving? :cheers:
 
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Traxx

Well-Known Member
Messages
682
Location
PNW
I can change a lot of filters in the time it takes to wash, wait on it to dry, and then oil one K&N.
 

mdocod

Well-Known Member
Messages
61
Location
Colorado Springs, Colorado
Because the K&N filter medium is 5X thicker than a typical dry paper filter, it has 5X more surface area (a paper filter must do it's job in 1/32", and K&N has 1/4" to do the same job). THAT is why it flows so much more air, NOT because it is not filtering as well (which is the often claimed argument against K&N).

"thickness" of the media doesn't count towards surface area. Filter media depth does have value in and of itself. In the case of a K&N, it is depth that provides the opportunity for small particles to interact with and cling to the oiled surface of the fibers in the filter, however, we can't measure filter media depth and directly compare it to the surface area of paper media filters, which operate on a different principal. Many pleated paper filters have far more surface area than a comparable sized K&N, but operate on a different principal of filtration. With that being said, in the example of the H3, most of the paper filters I have seen are not "old school" style with lots of paper pleats, but rather, a low pleat count "matted/thick" material. I think in this comparison, the K&N may actually have similar media depth to the OEM filters I have seen for the H3, but more pleats!!!

The "claimed arguments against K&N" are based on actual testing. K&N filters let more fine particles through than good paper filters. This has been demonstrated in numerous scientific tests published on the web. Is it a problem? That's for each to decide on their own as no testing has been able to definitively show a correlation to increased engine wear. I've seen it show up as increased silica in my own UOA's back when I tried a K&N filter, and decided to go back to paper on a previous SUV. With that being said, on the H3, just looking at the standard paper filters for these, I'm not convinced they are apt to be any better than a K&N for filtration as they appear to have less surface area. I suspect the "stock" filter design here is designed to hold more quantity (depth loading) and be more tolerant to accidental water ingress. Also, with skids, rock sliders, and 35s, I may start to care less about filtration and more about getting a few more HP if I can find it.



--------------------

As an example... In the pool industry, a sand filter might have 5 sq ft of surface area, but lots of media depth to work with for trapping particles down to around 20 microns. When clean, sand filters flow very freely. Meanwhile, a DE filter of similar physical size will have 60-100 sq ft of filter media, and much shallower media depth. A cartridge filter of similar physical size can have 300-500 sq ft of filter media, and very shallow media depth. Both the DE and Cartridge filters provide filtration down to ~2-4 microns. Media depth, in this example, doesn't do anything positive for filtration performance.
 

650Hawk

Well-Known Member
Messages
480
Location
SoCal
You are correct, the "5X thicker medium" does not correspond directly to a 5-fold increase in airflow, although it does have an effect on surface area, depending on the media. I was simply pointing out that the different medias filter in different ways, i.e. surface loading vs depth loading, as you clarified, and that increased airflow does not automatically correspond to less filtration. The oft heard claim that "It is letting more air through so it HAS to be letting more dirt through" is not valid; surface area, media thickness, type of media...it all works together to affect both filtration and airflow. And yes, some of the arguments against the K&N are based on actual testing, but often you have to look at who/what is behind the testing, as well as what level of filtration (microns) is actually necessary for an internal combustion engine. In other words, is the testing actually relevant to real world use, or designed to elicit a specific result? I have driven a number of vehicles to 300,000...400,000 miles, and more. If they were ingesting dirt, they would never have reached those numbers.

With the real world experience that I have with K&N over the past 50 years, on countless vehicles, I'll continue to use them without hesitation. I know the difference in performance that they have provided me (measurable, not seat-of-the-pants), as well as the squeaky clean intake tracts after even the worst desert dust/silt conditions (which has NOT always been the case for me using other filters).

As always, YMMV. :cheers:
 
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alrock

El Diablo
Staff member
Messages
10,442
Location
Scottsdale
Curious about all of this - is there a concern that the H3 engine is not getting sufficient air that a change in the filter alone will produce a measureable result? Would a dyno test show an increase of X horsepower?

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JPaul

Well-Known Member
Messages
2,400
Location
Way up north, UT
For the I5 I doubt you'd notice anything, it's the same filter for the I5 as it is for the much larger V8 I think, or they're very, very close to each other in size and surface area. The V8 you might see an improvement, but generally it's only at higher RPM where it needs a much greater volume of air. Unless you're redlining your engine all the time, the increase in airflow won't make much of a difference. It does reduce the pumping losses with the lower resistance, but not by enough that it'd be measurable in real world usage I think. It's still going to fall back to a personal choice of trying to squeeze every last pony out of the engine, versus longevity from consistent and improved filtration and peace of mind (provided you use an OEM filter and not something like a cheap STP or some garbage).

Personally I'm using the OEM filters because they're dead simple, take the old one out and put a fresh one in. Done and no worries about too little or too much oil. And I can keep a spare with me in case the first one gets clogged up on dusty tracks and longer trips, or if somehow it gets wet. I've used KN filters in the past on other vehicles, and they're great and all, but I got tired of spending so much time cleaning them and waiting for them to dry and then re-oiling them correctly. I didn't like having to make sure I wasn't going anywhere that day if I needed to clean my filter.
 

650Hawk

Well-Known Member
Messages
480
Location
SoCal
Agreed, for most applications you are not going to notice a difference, although that is not the case with a motorcycle or ATV. For me, I like the K&N on my larger vehicles (Hummer, Tahoe, etc) for a couple of reasons; I know that it is filtering as well as the stock filter, I know that I have increased airflow, it lasts 3-5 times longer before it needs cleaning, and since I have other vehicles, waiting a couple of hours for it to dry is a non-issue; I can still go somewhere. But there is definitely something to be said for the tried and true simplicity and consistency of a dry OEM filter!
 
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Mr_Rich

Well-Known Member
Messages
636
Location
High Desert & Santa Maria
This brings up the thought that there was a "doughnut" on the intake side of the airbox. This part was smaller on the I5 than the Alpha. Probably more than one of us swapped out our I5 part for the Alpha part. Probably a minuscule difference in this mod from long ago.
 

JPaul

Well-Known Member
Messages
2,400
Location
Way up north, UT
This brings up the thought that there was a "doughnut" on the intake side of the airbox. This part was smaller on the I5 than the Alpha. Probably more than one of us swapped out our I5 part for the Alpha part. Probably a minuscule difference in this mod from long ago.

If you're talking about the duct that goes from the air box into the fender, I wouldn't pull something like that out. Part of its job is to seal the inlet to the fender wall to prevent pulling in air from the hotter engine bay, and then with the design of the inlet it's shaped to provide a smooth path for air to flow in. Taking it out can introduce not only hot air from the engine bay, but also turbulence that could actually restrict the airflow, especially at higher RPM.

Now if you replaced the inlet from the I5 with one from the V8, you'd be cooking with gas. :)
 

Mr_Rich

Well-Known Member
Messages
636
Location
High Desert & Santa Maria
If you're talking about the duct that goes from the air box into the fender, I wouldn't pull something like that out. Part of its job is to seal the inlet to the fender wall to prevent pulling in air from the hotter engine bay, and then with the design of the inlet it's shaped to provide a smooth path for air to flow in. Taking it out can introduce not only hot air from the engine bay, but also turbulence that could actually restrict the airflow, especially at higher RPM.

Now if you replaced the inlet from the I5 with one from the V8, you'd be cooking with gas. :)

Way too wordy in the first paragraph; Inlet duct 25872511 replaced with inlet duct 25872521. That's all it boiled down to...
 
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