Diff questions (1 Viewer)

[scottryana]

I know that this has been batted around before and I think the @just differentials guys even built their 70 series this way, but I am kind of having a tough time wrapping my head around if it will actually work.

I understand that 80 series like 94+ are Full Float rear axles, in stock form they are 27 spline pinions and 30 spline axles. Their diff gear ring bolt pattern is also smaller than 98+ axles.

But 98+ axles in 4.30 and 4.88 are semi-float, with 32 spline pinions and 32 spline axles.

To make a stronger axle is it possible to use a 98+ carrier and gears in a 94-97 housing, get the 32 spline pinion and custom 32 spline full floating axles?

Is there an auto locker, detroit locker, truetrac, limited slip etc for the 98+ rear axle? Seems awfully silly but a 32 spline pinion seems like it would be worth it over a 27 spline and 32 spline vs 30 spline axles might be nice once power and grip start going up.

 

[inkpot]

Have you thought about a Tundra 10.5” setup?

 

[scottryana]

Well that would require a bit of fabrication. I was kind of thinking out loud in that this could be a nice mod for everyone.

If you are going to add lockers and regear anyways, why not just use the 100 locker, and 100 gears and get the 32 spline pinion and 32 spline axles with it. An ARB is the same price either way and you could get the same gear ratios. The only hold up as I see it would be the 32 spline rear axles as the 100 are semi float and the 80 is full float but pretty easy to get a full float axle made up.

 

[I Lean]

@cruiseroutfit , have you looked into this possibility at all?

As much as I like the idea of a FF rear end, I don't think the 32 spline SF axles are known to be breakable....and they're still used in the 200 series, behind the 5.7. I know the Canguro Racing guys have a BUNCH of off-road race miles on their 200, with no rear axleshaft failures I'm aware of. So you might be creating a solution in search of a problem.

 

[scottryana]

No the solution would be stronger pinion, and stronger shafts. I know there have been broken 30 spline axles, and why not get much stronger pinions too? Like I said if you are already going to do lockers and regear why not? But you can see the 32 spline has a lot more beef than the 29 spline and our stock pinions are 27 spline.

@cruiseroutfit , have you looked into this possibility at all?

As much as I like the idea of a FF rear end, I don't think the 32 spline SF axles are known to be breakable....and they're still used in the 200 series, behind the 5.7. I know the Canguro Racing guys have a BUNCH of off-road race miles on their 200, with no rear axleshaft failures I'm aware of. So you might be creating a solution in search of a problem.

 

[cruiseroutfit]

I've never gone the direction you're headed but before Nitro had 100 specific gears we used to use 8x differentials with 32 spline side gears and they bolt right into a 100 axle so no reason the 100 carrier won't bolt in the 4x/5x/6x/7x/8x housing with custom shafts.

 

[I Lean]

No the solution would be stronger pinion, and stronger shafts. I know there have been broken 30 spline axles, and why not get much stronger pinions too? Like I said if you are already going to do lockers and regear why not? But you can see the 32 spline has a lot more beef than the 29 spline and our stock pinions are 27 spline.

I guess what I was originally thinking was "just swap in a 100 series axle", but that wouldn't really work with the differing width and lug pattern.

So....proceed.

 

[ajax1]

Yes you would need the axle flanges changed over to the 6x139 pattern, so custom shafts, slee also did this on the blueberry I believe

 

[Letsgomoreplaces]

Yes, this is what I ran in the BJ73 (80 series rearend). I'm also running the same in the Trakka but with the original rear axle housing.

We offer all the stuff you need to do it. The axles will be a custom full float setup we have that are bolt in with drive flanges that have extra holes to add more dowel pins.

For me its worth it for the later gearset. 32 spline pinion is huge, but also since its not through-bolt, the teeth extend further to the I.D. of the ring gear for much more tooth contact (20% more than dana 60) I probably didnt need it on the troopy build but its a huge strength increase within the confines of the factory axle housing.

 

[ajax1]

And I think the newer nitro 5.29s you can get 29 spline pinion? You need diff flange to @cruiseroutfit ?

 

[scottryana]

This is exactly what I was thinking, great to hear! I know this is a stretch but I noticed Mark4x4 has 3.90 gears for the 98+ setups does Nitro have a 3.90? Or I guess is 4.30 the highest ratio with the 32 spline?

Yes, this is what I ran in the BJ73 (80 series rearend). I'm also running the same in the Trakka but with the original rear axle housing.

We offer all the stuff you need to do it. The axles will be a custom full float setup we have that are bolt in with drive flanges that have extra holes to add more dowel pins.

For me its worth it for the later gearset. 32 spline pinion is huge, but also since its not through-bolt, the teeth extend further to the I.D. of the ring gear for much more tooth contact (20% more than dana 60) I probably didnt need it on the troopy build but its a huge strength increase within the confines of the factory axle housing.

 

[landtank]

Yes, this is what I ran in the BJ73 (80 series rearend). I'm also running the same in the Trakka but with the original rear axle housing.

We offer all the stuff you need to do it. The axles will be a custom full float setup we have that are bolt in with drive flanges that have extra holes to add more dowel pins.

For me its worth it for the later gearset. 32 spline pinion is huge, but also since its not through-bolt, the teeth extend further to the I.D. of the ring gear for much more tooth contact (20% more than dana 60) I probably didnt need it on the troopy build but its a huge strength increase within the confines of the factory axle housing.

A little off topic but you guys have been supplying the 2002 spec pinions for the front 8" gear sets for a while now. And I can't understand why you don't include the proper oil slinger for the front of the 80s. I've talked several times to your guys and they don't seem to understand what I'm saying.

For me I just order one from Toyota as I know I need it, but I had a friend come by and even though I specifically told him we needed it he didn't quite understand why and since your guys made no mention of it we came up short on what was needed to finish the job.

Or am I missing something.

 

[Letsgomoreplaces]

This is exactly what I was thinking, great to hear! I know this is a stretch but I noticed Mark4x4 has 3.90 gears for the 98+ setups does Nitro have a 3.90? Or I guess is 4.30 the highest ratio with the 32 spline?

We offer 4.30 4.88 and usually have 3.90 and 4.10 OE takeouts as well

 

[Letsgomoreplaces]

Generally omit or quick grind out. Or new OE, unfortunately we have not had a bulk source, and the question has only come up a few times out of thousands of thousands. I do see your point though.

A little off topic but you guys have been supplying the 2002 spec pinions for the front 8" gear sets for a while now. And I can't understand why you don't include the proper oil slinger for the front of the 80s. I've talked several times to your guys and they don't seem to understand what I'm saying.

For me I just order one from Toyota as I know I need it, but I had a friend come by and even though I specifically told him we needed it he didn't quite understand why and since your guys made no mention of it we came up short on what was needed to finish the job.

Or am I missing something.

 

[scottryana]

Thanks! Give me a little to recover from my last spending spree and I will be giving you a call. Thanks for the support and all that you guys do.

We offer 4.30 4.88 and usually have 3.90 and 4.10 OE takeouts as well

 

[auttiman]

You could always buy a dynatrac 80 with 40 spline full floaters.....course, they're not cheap.

 

[scottryana]

Nor is it bolt in.

You could always buy a dynatrac 80 with 40 spline full floaters.....course, they're not cheap.

 

[cruiseroutfit]

And I think the newer nitro 5.29s you can get 29 spline pinion? You need diff flange to @cruiseroutfit ?

Correct, we stock the Nitro gears and the 29 and 32 spline flanges to run them

 

[cruiseroutfit]

A little off topic but you guys have been supplying the 2002 spec pinions for the front 8" gear sets for a while now. And I can't understand why you don't include the proper oil slinger for the front of the 80s. I've talked several times to your guys and they don't seem to understand what I'm saying.

For me I just order one from Toyota as I know I need it, but I had a friend come by and even though I specifically told him we needed it he didn't quite understand why and since your guys made no mention of it we came up short on what was needed to finish the job.

Or am I missing something.

Fwiw, our 29 Spline Pinion Flange Kits have the slinger, part# PN4121429

 

[Locked79]

@scottryana 32 spline full float axles are available out of a 105 series. Since 105s and 80s use the same housing, maybe they would work.

Here's a 105 long side