Re-Gearing with Yukon- pinion shims? (1 Viewer)

[kirk]

I am in the process of regearing my rear axle to 5.29's Yukon brand. I purchased them from specter b/c they were the only ones that had them. The instructions are generic and they say nothing specific to the 80series diff. Diff gears that I have set up in the past have a CD "checking distance" scribed on them. That gives me a idea of where I need to start regarding pinion shimming. The yukons dont and I set them up using the same shims that were in the factory gears. After doing this the bluing told me I was way to deep. I set them to the min shim listed in the FSM and it also told me the pinion was too deep.
So then I called Randy's ring and pinion the owners of Yukon. A guy in their install shop said he starts with a .015 shim on the pinion. That would be 1/3 the thickness of the thinnest factory shim.

Can anyone confirm this?

Thanks

Kirk

 

[Letsgomoreplaces]

shim

.015" is typical of the fj40/fj60 etc. The 80 series diffs typically setup closer to stock (about .045). I would suggest using the stock shim as the starting point, check pattern, and adjust as necessary. How long ago did you get the gears? We have had 5.29s in stock for quite some time as we get them directly from an actual gear mfg.

 

[kirk]

Thanks for your help!

I thought that was crazy.

*****Do you know anything about what the gear cutter uses as the "CD" or pinion depth dimension that they set to check from???? I have a pinion depth gauge.

I have owned them for probably 8mos. Beno and I checked with you at that time and you have 4.88 but no 5.29's

When I break this set I will buy a new set from you!

Thanks

Kirk

 

[alia176]

isn't the CD = center of the ring gear (or the axle) to the head of the pinion gear? Though, I'd love to know how you measure this in real life!!

 

[kirk]

You can do it easy with the right pinion depth checker. Also on toyos the split in the cap is on the dead center of the bore. so if you span the caps with a precision ground bar then depth mic it and subtract the thickness of the bar you got the number.

 

[concretejungle]

wow you guys are talking greek to me.

 

[alia176]

You can do it easy with the right pinion depth checker. Also on toyos the split in the cap is on the dead center of the bore. so if you span the caps with a precision ground bar then depth mic it and subtract the thickness of the bar you got the number.

I'm going to have to "wing" this one when I go to 4.88s! Looking at Zuk's site, he skips this step and goes straight to the pattern using factory pinion shims. If the pattern is too shallow/deep, then he starts messing with different shims.

 

[azzzuki]

I'm going to have to "wing" this one when I go to 4.88s! Looking at Zuk's site, he skips this step and goes straight to the pattern using factory pinion shims. If the pattern is too shallow/deep, then he starts messing with different shims.

I tryed to get Zuk to set up my gears and he said NO!
Said he only did pickups and detroit's.....???????
so i did them my self!
ended up with a pretty good patren but still have a faint noise in the rear under load.
I think its just Yokon gears.

 

[Letsgomoreplaces]

gears

Thats why we dont use yukon LC gears.

But, as far as setup, the pinion depth gauges dont do much good. They take longer, and you still need to set by pattern. I have built over 5000 diffs, including 100's of LC diffs, and your best bet is to start w/ stock shim, run pattern, then change if necessary. Changing the depth 3 times still takes less time than using a pos depth gauge. Since we do so many, we keep track of starting depths for most diffs.

I tryed to get Zuk to set up my gears and he said NO!
Said he only did pickups and detroit's.....???????
so i did them my self!
ended up with a pretty good patren but still have a faint noise in the rear under load.
I think its just Yokon gears.

 

[richj11]

your best bet is to start w/ stock shim, run pattern, then change if necessary.

I just road tested my rig after installing 5.29's and ARB's. Everything, BTW was purchased from these guys http://www.ringpinion.biz/ . shameless plug


I had never done a gear setup. Read everything I could find about the subject, including lots of ZUK's write ups.

Both front & rear ended up getting good patterns (In my novice opinion!) with the stock shims reused.

Rich J