10bolt front diff tech

[atvspeed4]

Seeing the diff is all the way to the gasket surface do u feel like a substantial amount of strength has been given up

I think we are still safe, we have not touched the material around the carrier bearings and we are pressing in a solid 1.25 long bearing race for the stub shaft to sit in.

Cost isn't as bad as expected. If we paid our local shop to build it for us it would run around $950 including shafts I think. The big deciding factor is if a stock shaft can be resplined for the 10 bolt carrier.

I know that does not include a locker or gears but isn't that close to the cost of a stock iron housing? Guess you are right that is kind of expensive though considering I know people who wheel $2,500 rigs lol. Well I don't want to give up yet I love wheeling my h3.

 

[rsc]

If you can get this to work AND it didn't need to go under a Rancho Lift then I would be all over this one. Keep up the great work you're doing, I wish I had the time or shop to give it a try myself but if it pans out then I'm gonna find a way to get one under my truck! (and regear it for a set of 37" tires! )

 

[rsc]

If the stock shaft needs to be resplined to match the 10 bolt carrier, would it be possible to cut and weld the two necessary ends together or does is need a splined coupling over the stock splines? Drive shafts are rewelded all the time and they run strong and true, right? Even if the weld is the weak point it could be that "frangible link" in the front that breaks before something more expensive goes. In that case, I would just own an extra set for spares.

 

[atvspeed4]

If the stock shaft needs to be resplined to match the 10 bolt carrier, would it be possible to cut and weld the two necessary ends together or does is need a splined coupling over the stock splines? Drive shafts are rewelded all the time and they run strong and true, right? Even if the weld is the weak point it could be that "frangible link" in the front that breaks before something more expensive goes. In that case, I would just own an extra set for spares.

Oh sorry should have written stock long side shaft of aam 8.25 front diff. Otherwise the stub shaft alone is going to be $300-400 custom part.

 

[4speedfunk]

Damn. That's not a huge surprise but, tough news all the same. It seems the H3 just won't cooperate with any ideas. The pile of chopped axles gets taller!

I was going to suggest you try the Dana 44 casting because its much narrower...tube-to-tube. However, if you have shaved away at the ten-bolt casting...you're probably close to the same dimension anyway. The two share the same basic size & shape cover so, you're probably in the same neighborhood when it comes to overall finished width. I wouldn't attempt an IFS upgrade without the Rancho (or building something similar), as it really opens up some valuable space under there. I think Digger was the only guy to do something like this without a lift. Space was very critical with his swap (even more so) because he used a high-pinion IFS Ford pumpkin. With this set-up...the yoke was way up high, right next to the oil pan sump. Like you, it was getting into the oil pan so he used different length half-shafts...and scooted the pumpkin over to the passenger side a tad to get it to fit. I think the front driveshaft may have even been sloping up-hill!

BTW...here's a shot of the Ford IFS D44. I'm showing this just for reference...its basically what we've all been trying to make...a stubby diff with seals in each side of case. However it's set-up for drivers-side drop, with the seal on the driver-side. The passenger-side (hidden in this photo) has a machined surface where a tube bolted to it, very much like the AAM-7 does (but opposite end). But perhaps you could mimic the d.s. seal situation and make something similar on the p.s.? It would basically be a poor-man's version of the Currie IFS chunk shown earlier in this thread (NOTE its sitting upside down in this photo)...



On the re-splining: You can probably have custom stub shafts made for very little. Seems like a very simple part to make...and even less material. Nothing exotic, I assume. All you're looking for is a GM IFS flange on a short shaft with 10-bolt splines on the end, right? Were you planning on using C-clips? I don't know much about re-splining other than it takes special equipment and its usually done BEFORE a shaft gets hardened. Not sure if cutting down full-size IFS shafts is possible due to taper and this hardening issue (if thats even an issue). Anyway...we appreciate your efforts. You're not the first guy to take a swing at this. If we keep sharing our experiments...sooner or later...somebody will get this swap figured-out.

 

[atvspeed4]

I remember reading about Diggers swap when he first did it. If I ran a custom cv like him we would be done by now. I do not like the idea of making a cv shorter as it increases axle plunge and increases the angle of the cv. Fortunately the seal and bearing we figured out. I just turned a bearing plug that is pressed into housing and uses the aam 8.25 bearing and seal. Can't use a normal cut to size flanged shaft its the wrong shape and won't get close enough.

 

[atvspeed4]

Just wanted to bump this thread for ideas. Looks like we will be diving back into this soon. Our final conclusion is you cannot use a GM 10 bolt or dana 44 without making custom shorter CV shafts as the pinion will hit the oil pan. With the rancho kit this may be different. We are going to try the HP Dana 30. This is MUCH stronger than the low pinion that came on the H3 and will allow down to 4.88 gearing which is at least a little better.

 

[bebe]

It is smaller than the current set up, what about a Dana 35?
http://www.therangerstation.com/tech_library/Dana30.htm

 

[atvspeed4]

It is smaller than the current set up, what about a Dana 35?
http://www.therangerstation.com/tech_library/Dana30.htm

Interesting read! The question that we are trying to figure out is: Will the High pinion cast steel dana 30 be stronger than the cast steel low pinion that comes in the alpha since it will be running on the drive side of the gear instead of the coast side. Are the Dana 35 fronts in the ranger high pinion or low pinion like the common 35 rear? I Do know that the 35 fronts in the explorer and ranger use an aluminum center section unfortunately.

I wish I could just drop my 3 off and have your suspension installed... someday I guess!

 

[bebe]

Well, that was my concern, I see that they have a case deflection issue as well. So I think there are so many D35 applications, you'd need to research which one will work best. I think the Waggy was a PS drop, but would need to research what years. I'd hate to see it require a very narrow range of applications.

Throughout the 1990s Ford used the Dana 35 as a front axle. In both TTB and full IFS variations. These units also follow Ford's tradition of using high pinion, reverse cut units. Dodge used this front axle only for a few years in Dakotas and Durangos.

 

[bebe]

And - Rick and I have talked occasionally about the Toyota 7.5" front. It's strong and a drop out, gears can go to 5:29's.

 

[06 H3]

I actually thought about that when I saw mayhem metal works toyota...some questions popped in my head. Is it structurally stronger or is it just holding together and being a stronger piece because those toyotas weigh less then ours. Not sure what the answer is, just thinking out loud.

 

[bebe]

4 runners GVWR is pretty dang close. And yes - they are waaaaay stronger than an AAM725

 

[backcountryislife]

4 runners GVWR is pretty dang close. And yes - they are waaaaay stronger than an AAM725

That said though, a good buddy of mine who wheels his FJ on 35's has been through 3 front diff's, and would like another solution for his as well, so though it may be stronger, I feel it's probably only marginally so. The gear options alone would make it worth the swap though imo.

 

[gfbh3t]

I talked to Currie, and G2 at 4wheel parts fest and called Dutchman, just differentials, Hazzard Fabworx all told me cost to much without even telling me a price to make a custom front diff. Nitro Gear said they would need an order for 200 ring and pinon sets before they would think of making 5.13 gears. And I'm in a hotel about a mile from Randy's Ring and Pinion and went to the parts counter there and they told me 4.10's were the biggest made for the h3 so I left there. So a high pinion straight axle coil spring setup looks promising.

 

[4speedfunk]

Gfb...I think you would love the gearing change (SA or IFS). You're rig is already quite bad-ass but, if you're like me...you've probably noticed some gearing issues with the 5cyl. If you're ever passing thru Indy again...drop me a line. You need to drive my rig, and see how you like the 5.13s & 37"s. I think Bebe is running the same ratio and I can't speak for her but, on my end...these gears just feel "right" with the 3.7L. You can set the cruise at 65mph, the motor only revs to 2000rpm, and the AT stays in 4th gear...the way its supposed to. If anything, you have to re-train your throttle foot so you don't whiplash it every time you take-off! Gears this low are very "sensitive" to your foot, even with big tires. And needless to say...the 4:1 low range makes me giggle every time I use it.

I'de be very surprised if you could find anybody to make custom gearsets for the AAM-7, especially that low. A 5.13 D44 R&P uses 41 & 8 teeth, and if you were to mimic that on the AAM-7, I think it would be pushing the limits of tooth size. I know there are Toyotas and Dana 30s that run a similar tooth arrangement but, the 5500lb H3 probably needs more tooth contact area than the any of these can safely offer. I feel a 7" ring gear is just too small to run a ratio that low, in a vehicle this heavy, with a tire size this big. I actually think my current axles (Dana 44 and 8.6 GM) are at their limit...so I go easy on them.

I think if you kept the build on the mild side, a custom Dana 30 (or Toyota) IFS might work just fine with 33" tires. However, its hard to justify a "mild" full-custom IFS build to only run 33" tires. No easy answer.

 

[gfbh3t]

Great minds think alike was going to tell you I wanted to stop by on my way home from Seattle. Thought about the Toyota diff also but no 5.29 gears for the rear axle

 

[bebe]

That said though, a good buddy of mine who wheels his FJ on 35's has been through 3 front diff's, and would like another solution for his as well, so though it may be stronger, I feel it's probably only marginally so. The gear options alone would make it worth the swap though imo.

The 4Runner straight axle is completely different than the IFS FJ axle. Rick ran 36's on his for 15 years and never broke an axle in the rocks. They are not aluminum like the IFS clamshell. And I misspoke earlier, they are 8" the IFS is the 7.5. So, smaller than a 44 and a bit bigger than the 7.25.

It could work. It would still require custom work, but....

 

[bebe]

Great minds think alike was going to tell you I wanted to stop by on my way home from Seattle. Thought about the Toyota diff also but no 5.29 gears for the rear axle

West Coast Diff, (Sierra R&P) makes 5:29's for the 10 bolt, and the 44. IIRC.

 

[atvspeed4]

The 4Runner straight axle is completely different than the IFS FJ axle. Rick ran 36's on his for 15 years and never broke an axle in the rocks. They are not aluminum like the IFS clamshell. And I misspoke earlier, they are 8" the IFS is the 7.5. So, smaller than a 44 and a bit bigger than the 7.25.

It could work. It would still require custom work, but....

Thats the diff I was looking at. My friend has a truggied tacomo on 37" military take offs and 12 bolt wheels. No issues with the ring and pinion. Thanks for the suggestion I think the dimensions of that diff would work much better!

 

[backcountryislife]

AH... got ya, thought you meant the yota IFS diff.

 

[06 H3]

In California there's Toyotas everywhere. I need to go to a junkyard and find one. 8in ring gear isn't the best but its better then now.

I'm tempted to ditch the stock ifs and go solid axle but I'm not giving up yet. We now have steering solutions and more coming (think what's outboard of the rack ) if we can get a diff solution also I think it will help a lot! I just need to convince myself that dumping money into a slightly bigger R&P is worth it. Enough for 37s and a regear. I just don't want it to be a ticking time bomb.

Lastly I think fitment will be easier especially because its already ifs and the yota track width is smaller. We just need to make sure the lengths are perfect for plunging cv's and to match the stock setup.

Ill patiently be waiting and I will start searching for more info on the yota ifs diffs

 

[gfbh3t]

06h3 check out. Eric's Toyota dfferential info-4x4 wire .

 

[bebe]

Erik "B" is a very good friend of ours and lives here in Auburn. He and Booger Welds (Paul Ryan) have contributed more to toyota tech than just about anyone I know.

The axle I'm referring to is the straight axle, 8" toyota front, and the application would be to chop it down and use it like mine, with 1 ton shafts.

We want nothing to do with the IFS Toyota front, either the 4runner or FJCruiser.

 

[atvspeed4]

We tried clearing 1 ton cvs with stock suspension and it will not work. While it physically fits into the wheel bearing and knuckle the boots rub really bad in several places and no matter how you adjust the cv it rubs. It gets even worse when you turn the knuckle. The straight axle toyoda front with the 8" is a high pinion out of a landcruiser right? I am pretty sure with stock suspension it will not fit as you will hit the oilpan just like we discovered with the GM 8.5 LP