Chopping a 10-bolt for IFS...

[4speedfunk]

Figured this was worthy of its own thread. Lots of talk on this subject and I'm sure it can be done but, my experimentation quickly made me realize that there are better choices and better ways to beef the IFS. None are simple or cheap but, hey....if it were easy, everyone would already be doing it.

First, I took a couple pics of a Dana44 housing next to the 10bolt. As most already know...these axles are very common and they can be found in ANY GM truck from 73-91, in various forms. There's alot to mention about using these for SAS reasons but, since this is CHOP thread...I'll limit the ramble to that purpose. The two housings can easily be identified by the cover shape. If you remove the cover, you can see the 10-bolt has (2) locating holes drilled into the cover gasket surface. (more on this later)...and the Dana does not...


Having decided on the 10bolt...I moved-on to do some more investigating. The first pic shows the basic plan of attack...I want to cut the 10b housing down to match the size of the AAM-7. The second pic shows the drastic size difference of the cases...particularly the width between the journals. The AAM-7 looks almost "cartoon-ish" and clearly has no business under a 4x4 vehicle. The third pic shows the ring-gear size...7.6" vs. 8.5. The shaft you see sticking out of the 10-bolt carrier is actually a stub shaft from an AAM-7. This was the entire basis for choosing the early 28-spline version of the 10-bolt...


Moving on...I grabbed a saw-zall and made quick work of the chop. At this point I'm merely trying to cut it down to make it easier to handle. As you can see...plenty of tube there. After the chop...it started to look more like an IFS. BTW...I kept the inner-C's for an upcoming Hi-Pinion Solid axle project.


Going back to the AAM-7, I took a look at the seal and bearing arrangement. This is what I'm trying to duplicate on the 10-bolt housing. The idea being to make the 10b capable of receiving a stock H3 half-shaft...(theoretically possible because they share the same splines)...


Uh-oh. I'm apparently I'm out of "photo" space, and I cannot add any more. (too bad, it was just getting good!).

 

[gfbh3t]

Keep going !!

 

[4speedfunk]

Sorry G....I'm too stupid to figure out how to delete older photos from my profile.

Maybe somebody can educate me.

:emb:

 

[gfbh3t]

would not be me. it is tough enough for me to post a reply.

 

[4speedfunk]

Loud & clear. Cavemen have no place on the net.

 

[Gunner_45]

Are you uploading them to your album and then referencing them here in this thread?

If so, Alex may have to change something as admin that I can not get to as a Mod.

Other option would be to get you a PhotoBucket account for free and just post the image code here.

This thread is too good to stop just because of quota limitations.

:gaah:

 

[06 H3]

Yea lets figure out this picture thing so we can continue! Lol

 

[Schwarttzy]

Looking forward to more photo's! Can't wait to get sometime to chop mine up.

 

[MaxPF]

Going back to the AAM-7, I took a look at the seal and bearing arrangement. This is what I'm trying to duplicate on the 10-bolt housing. The idea being to make the 10b capable of receiving a stock H3 half-shaft...(theoretically possible because they share the same splines)...

Unfortunately, I don't think that is going to be possible, especially on the short side. The shafts for the 7" are designed for the spacing between the seal, support bearing, and side gear on that housing. Everything is simply wider on the 10b. Even if you machined down into the housing on the short side I'm not sure you will get it that close.

Also, since the basic carrier is wider, it is going to push each side out an amount equal to 1/2 the width difference between the two carriers. There may be enough travel in the half shafts to accommodate this, but you'd need to measure it to make sure. Even if this is the case, the above problem still remains.

 

[06 H3]

Using custom stub shafts and an H2 axle shaft what housing would you recommend while still using the stock crossmember

 

[amrg]

It seems uploading pictures on this thread is a more difficult issue than the build itself

 

[4speedfunk]

Haha...so true. If I could load the rest of the pictures, you would see the problems incurred and why chopping a 10-bolt doesn't really work. Max is on the right track, and it makes much better since to run flanges and bolt-in half-shafts (Bebe style). Trying to mimic the seal and bearing arrangement of the AAM-7 is nearly impossible because it is so compact. Any bigger diff you choose will result in the same basic problem: The splined snout of the stock half-shaft is simply too short to fully insert into the carrier.

 

[4speedfunk]

It must have been a problem with one of my photos. Here's a continuation:

When doing an IFS chop, don't forget to remove the inner axle seals so the oil can flow out to the CV support bearings. In a solid-axle arrangement, the axle tubes run dry and its very common to find gobs of mud and crap stuck inside the axle tubes. I'm getting very good at assessing an axle's history by reading these clues. I'de say this axle has been wheeled in Georgia or Alabama (red clay)...


We used a band saw to chop the spring perch...works pretty good as long as you have a big one...


Next we fabbed a milling plate out of 1/2" steel. This plate has (2) dowels that fit the alignment holes in the face of the 10-bolt pumpkin. By using this plate, you can insure that the milling process is registered to the factory surfaces of the pumpkin. This means you get a square surface that is a true 90-degrees from the axle centerline. This is critical for bearing and seal alignment. We shaved right up to the edge of the front cover gasket, and you can see the milled surface in the third photo...


Now this is where I put the brakes on the project. After milling, I realized that I was a full 1.5" away from where I needed to be. The width of the 10-bolt carrier requires a 5.5" dimension from the carrier splines to the new CV seal. By comparison...the AAM-7 only needs 4.0". So, unless you can find a 28-spline CV joint with a longer input snout...you're done. (and even if you do...it will be different from the other side, and you'll have to carry two different trail spares...Digger-style). This goes against my original requirement of using 100% stock outer IFS parts...


To resolve this, I looked at adding a small coupler between the carrier and the CV support bearing...almost like a "socket extension". The male end would be captured inside the diff with a C-clip, and it would have a female end to accept the stock CV-shaft. However, a coupler requires a minimum of 3"...which would mean scooting the whole assembly further inboard. Faced with this extra complexity...and straying further and further from stock half-shafts...I took a day to think it over. If I have to make couplers to adapt to stock CV-shafts...I might as well make stub-shafts with flanges for bolt-in half-shafts. The price would be nearly the same, and it no longer makes sense to use a front 10-bolt (especially a 28-spline version). I feel the Dana44 or a rear H3 10-bolt would be more worthy of experimenting. This front 10-bolt casting was returned to the junk-pile, and many lessons were learned.

I still say it can be done. However, its enough work that you need to make sure the final product is worth your efforts. That means starting with a better diff to begin with, and committing ahead of time to use bolt-in shafts and custom flanged axles. Even if you get it figured out...you still have stock travel, rubber CV boots, a wimpy steering rack, non-greasable A-arms, and mounting issues. No matter how you skin the cat, it still ends up snow-balling into the Bebe rig (which is the right way to tackle the IFS problem). If somebody else wants to tackle the "cheap and easy" IFS upgrade, I'm all ears! Honestly I don't think there is such a thing, and that's why I'm switching gears to focus my efforts on solid axle swaps.

 

[06 H3]

thanks for all the work 4speed, I will think about it for a while. I am not sure if I wanna do the SAS. According to samco fab you can easily pull 8in of wheel travel out of a stock setup. The upper a arms will be greasable once I buy dwaines a arms. You still have lowers to deal with which can be upgraded. My biggest issue is cutting everything off the frame, going with a subframe or chopping it all off for a SA, its just no going back and I am not ready for that yet.

I havent had any steering rack issues, I just want stronger halfshafts, regear and a stronger front diff. whether its RCV halfshafts or H2 halfshafts I refuse to use either one without a stronger front diff. Atvspeed4 is gonna try and I may go pick up an axle, I just need to find a good machine shop then I can start investigating...

 

[gfbh3t]

4speed so what you are saying is I should through on some 37's and run them till I blow up my cast iron diff and then do a solid axle swap and everything will be good!

 

[4speedfunk]

Geno...that is a profound question. I would never tell someone to intentionally grenade their axle (although it sounds awesome!). I'm just saying that given the situation...given the choices you have...given the lack of a real cheap and easy solution...a solid axle is certainly do-able. I drive one everyday. Don't get me wrong...its a major undertaking. But, if you love your H3 and you love wheeling...its something to consider.

I also want to point out that grafting-on a 2500 series IFS is also a possibility. Nobody seems to push this idea but, I actually think it is a better alternative than a custom IFS. You would have to convert to a drivers-side T-case...but that also means you could get 2WD too. So...its worth looking into, IMO.

Ultimately...if you have concerns (I've wheeled with you!), go easy on the pedal. I got a nice AAM-7 sitting on the shelf and its got your name on it...should the need arise.

 

[gfbh3t]

That passenger side drop really complicates every thing. I've also thought of the 2500 front end since I drive one every day since 93. But i think the straight axle is most sensible. Or i need a beater h3 to start chopping apart. Toyota has a 7 1/2 passenger side diff with 5.29 gears that could possibly work but probably not any stronger.

 

[MaxPF]

...it no longer makes sense to use a front 10-bolt (especially a 28-spline version). I feel the Dana44 or a rear H3 10-bolt would be more worthy of experimenting. This front 10-bolt casting was returned to the junk-pile, and many lessons were learned.

One advantage of using a front axle, whether 10b or D44, is that the milled-down spring perch gives a nice large surface to mount a seal/bearing retainer in a left-offset IFS diff. Also, the oiling is a bit different on a front pig since the ring gear usually rotates in the opposite relative direction. OTOH, plenty of guys have built front axles using 9" Ford and 14bff rears with no oiling issues, so I doubt using a 10b rear would be an issue from that standpoint.

Even if you get it figured out...you still have stock travel, rubber CV boots, a wimpy steering rack, non-greasable A-arms, and mounting issues. No matter how you skin the cat, it still ends up snow-balling into the Bebe rig (which is the right way to tackle the IFS problem). If somebody else wants to tackle the "cheap and easy" IFS upgrade, I'm all ears! Honestly I don't think there is such a thing, and that's why I'm switching gears to focus my efforts on solid axle swaps.

That is the problem with IFS. A properly built IFS setup is going to require a centered diff (which creates clearance issues) and a lot of custom, pricey parts for adequate travel, strength, durability, and reliability. Although a SAS appears difficult to the uninitiated, it is actually an easy and comparatively cheap way to get a big boost in front end capability. If done right, any degradation in ride quality should be minimal, and degradation in handling non-existent. The only place IFS will really surpass a solid axle is high speed off-road travel. If that is your interest, then IFS is definitely the way to go.

thanks for all the work 4speed, I will think about it for a while. I am not sure if I wanna do the SAS. According to samco fab you can easily pull 8in of wheel travel out of a stock setup. The upper a arms will be greasable once I buy dwaines a arms. You still have lowers to deal with which can be upgraded. My biggest issue is cutting everything off the frame, going with a subframe or chopping it all off for a SA, its just no going back and I am not ready for that yet.

Meh, everyone's squeamish until they make the first cut :hack: After you get past the initial trepidation and get comfortable with the idea, it goes a lot easier.

As for travel, keep in mind that my truck has 12" of travel with a comparatively primitive leaf spring setup. If I were willing to change shock mounts and shocks I could get 16". With coil-overs, travel is limited to how high you can position your upper mount and the size of your wallet. OTOH, more than 12-14" is not really necessary for 99% of us. Again, things that are difficult and expensive to do with IFS are easy with a SA.

I havent had any steering rack issues, I just want stronger halfshafts, regear and a stronger front diff. whether its RCV halfshafts or H2 halfshafts I refuse to use either one without a stronger front diff. Atvspeed4 is gonna try and I may go pick up an axle, I just need to find a good machine shop then I can start investigating...

Most important question is what you want to be able to do with your truck. Depending on the answer to that question, your idea of strengthening the stock setup is either the best option or a waste of money.

4speed so what you are saying is I should through on some 37's and run them till I blow up my cast iron diff and then do a solid axle swap and everything will be good!

Geno...that is a profound question. I would never tell someone to intentionally grenade their axle (although it sounds awesome!). I'm just saying that given the situation...given the choices you have...given the lack of a real cheap and easy solution...a solid axle is certainly do-able. I drive one everyday. Don't get me wrong...its a major undertaking. But, if you love your H3 and you love wheeling...its something to consider.

Agree with everything he said ^^^

I also want to point out that grafting-on a 2500 series IFS is also a possibility. Nobody seems to push this idea but, I actually think it is a better alternative than a custom IFS. You would have to convert to a drivers-side T-case...but that also means you could get 2WD too. So...its worth looking into, IMO

Besides the obvious issue of being right-hand drop, the 2500-3500 IFS is obviously bulkier (9.25" ring gear), and it's width may be a problem. In the end, it is still an aluminum IFS diff, and I have seen them split in half under high load. Granted, this probably wouldn't happen in an H3, but I don't know if I would be keen on spending a bunch of money to swap in a larger aluminum IFS pig.

 

[06 H3]

I know that first cut is scary. it was for the spring over, I cant imagine doing the front...Max, going off of the ifs topic and onto leaf springs what's your take on springs going Into negative arch? I see your springs are pretty flat like mine. Great down travel! I can net 12 but shocks limit me to 10. I'd rather have nothing hanging below the axle so ill take 10 instead of 12...leaf springs are great at flexing. I just wanna know if I should bump it before negative arch

As for ifs, I do all types of terrain, high speed low speed, crawling, mud etc. it's done fine but if I do a SA would type of suspension would you recommend? I know leaf spring would probably suck up front for higher speed. They do well in the rear for high speed though. A lot of prerunners use them...

 

[4speedfunk]

It seems most everybody is flexy-this and flexy-that but, I don't subscribe to the "more flex is better" rule of thumb...especially if you gotta drive it around everyday. Rather than dumping the intelligent T-case and going old school...I kept the electronics functional, and that allows for a much milder build. As long as the TCS is working...you don't need mega flex or long travel. I'm not a hardcore wheeler by any means. In fact...I'm so gun-shy from years of wheeling the stock IFS, that I probably appear to be a sissy in the eyes of other solid-axle guys! But with a 4:1 low-range, 5.13s, lockers, and 37" KM2s...there is no need to stomp the throttle to the floor. Instead you just creep over anything you damn well want to. Nowdays I rarely ever back-up and do full-throttle charges like I used to. I'm more limited by my own common sense, than by my rig...and frankly, thats exactly where I want to be! Confidence is very seductive, and wheeling is so much more enjoyable when you know that your rig is no longer your weak link. Instead your own ego becomes the weak link, and its hard to keep it in check sometimes! Ha.

Now that I've logged five thousand miles on the SA, I feel pretty good about the it. It rides firm and handles well on the road. Off-road its downright STUPID capable. In fact...its way more awesome than I really anticipated back when I started it. Even sticking to the mild-end of the SAS spectrum...it came out way better than I ever thought (or wanted). I still got some changes and adjustments to make but, I'm slowly getting the bugs worked out. Here's a pic from just yesterday at a jobsite...



I drove 1-1/2 hours to get there, thru the remnants of a blizzard. I can honestly say there is no other vehicle I'de rather be driving in such conditions. The red H3 pulled in right after me, and the guy seemed to be completely aloof to fact that we had the same vehicles. I said "Nice Truck" and he sort of nodded and walked away...having no clue that I had done anything to mine. I'm still amazed at the number of people driving around H3's that have no idea what a unique and different machine it is from anything else. Jeez.

BTW...I accidentally found another SA H3 on Youtube the other day. This is #5 that I'm aware of, and you can clearly see how solid axles and high-speeds don't work too good together. I have no idea who built it but, it may be another ORE rig (Pro-rock60 & Fox COs)...
https://www.youtube.com/watch?v=FZ2F58RpAG8

I think we're gonna see more SA H3s in the near future. I already got all the parts stock-piled for my next one (including MaxPF's knuckles!)

 

[atvspeed4]

We picked up our 8.6" diff today. We found a 8.6" that has a slightly narrower housing with less webbing so it should go much better.

 

[gfbh3t]

4speed are you happy with the km2s

 

[06 H3]

H2 shafts or h3 shafts will be used?

 

[06 H3]

It seems most everybody is flexy-this and flexy-that but, I don't subscribe to the "more flex is better" rule of thumb...especially if you gotta drive it around everyday. Rather than dumping the intelligent T-case and going old school...I kept the electronics functional, and that allows for a much milder build. As long as the TCS is working...you don't need mega flex or long travel. I'm not a hardcore wheeler by any means. In fact...I'm so gun-shy from years of wheeling the stock IFS, that I probably appear to be a sissy in the eyes of other solid-axle guys! But with a 4:1 low-range, 5.13s, lockers, and 37" KM2s...there is no need to stomp the throttle to the floor. Instead you just creep over anything you damn well want to. Nowdays I rarely ever back-up and do full-throttle charges like I used to. I'm more limited by my own common sense, than by my rig...and frankly, thats exactly where I want to be! Confidence is very seductive, and wheeling is so much more enjoyable when you know that your rig is no longer your weak link. Instead your own ego becomes the weak link, and its hard to keep it in check sometimes! Ha.

Now that I've logged five thousand miles on the SA, I feel pretty good about the it. It rides firm and handles well on the road. Off-road its downright STUPID capable. In fact...its way more awesome than I really anticipated back when I started it. Even sticking to the mild-end of the SAS spectrum...it came out way better than I ever thought (or wanted). I still got some changes and adjustments to make but, I'm slowly getting the bugs worked out. Here's a pic from just yesterday at a jobsite...

View attachment 8121

I drove 1-1/2 hours to get there, thru the remnants of a blizzard. I can honestly say there is no other vehicle I'de rather be driving in such conditions. The red H3 pulled in right after me, and the guy seemed to be completely aloof to fact that we had the same vehicles. I said "Nice Truck" and he sort of nodded and walked away...having no clue that I had done anything to mine. I'm still amazed at the number of people driving around H3's that have no idea what a unique and different machine it is from anything else. Jeez.

BTW...I accidentally found another SA H3 on Youtube the other day. This is #5 that I'm aware of, and you can clearly see how solid axles and high-speeds don't work too good together. I have no idea who built it but, it may be another ORE rig (Pro-rock60 & Fox COs)...
https://www.youtube.com/watch?v=FZ2F58RpAG8

I think we're gonna see more SA H3s in the near future. I already got all the parts stock-piled for my next one (including MaxPF's knuckles!)

That may be the one in Utah! I think that one is more recent....I agree with flex and disagree. I agree too much is bad but some is good. For ease I want to keep the front end with stock mounting but strengthen it and aim for 8in of travel samco fab said they can pull 8 easily...I think a little bit of travel with our electronics and front end beef up I would be good to go and a regear too...

 

[atvspeed4]

H2 shafts or h3 shafts will be used?

We are shooting for 2500 shafts first but may have to go to 1500. We will see!