Solid spacer/shims for pinion preload

[Bret]

I am having a little trouble getting my preload correct with the pinion nut tight and wanted to make sure I wasn't overlooking something stupid.

The ring and pinion is a later style (new) that uses the crush sleeve, I am trying to use the solid spacer with shims instead. My solid spacer is approx 2.10" long with .10" in shims (all that came with the spacer) and when I try to tighten it up the preload goes through the roof. the part that is odd is the crush sleeve is approx 2.2" long and would have to "crush" to be set. So why in the heck when I start to tighten a solid spacer that is almost the same length my preload is hosed?

Just want to double check that I am not missing something before I just try to find some more shims.

thanks,
Bret

 

[kiwidog]

pinion preload.

Hi Bret,

Just put new bearings and Aussie locker into son's BJ60 yesterday.
Ready to drop the diff head back in this morning.

Pinion didn't have a crush sleeve. Just a small shim. Turned out that 0.135 worked out to be the right size. First i made a bigger one 0.190 on the lathe. Installed it and tighten the pinion nut to torque. Measured the end play of the now loose pinion with dial indicator. Subtract this measurement from the 0.190 -0.055 = 0.135. I then turned a shim to 0.134 and fitted to the pinion. The final shim ended up being 0.132 so I had approximately 0.002 to 0.003 of pre-load felt about right.

You could do the same thing with your crush sleeve. Add shims until you have a loose pinion measure, then subtract the measured looseness and make a sleeve that length less the pre-load you want. I think about 0.002 to 0.003 is about right with new bearings. Less if you re-use bearings.

Helps to have a lathe. but any machine shop could knock you up something in few minutes when you have the dimensions. Mine was 30 mm ID and 40 mm OD. by whatever length it turns out to be.

Hope this helps

Thanks jb

 

[Bret]

Thanks for the crush sleeve idea, I hadn't thought of that one. I'll give it a shot so at least I will know how much more I will need to shim.

 

[Pin_Head]

Preload is set with a thick (approximately 0.1 to 0.15 inch) "preload washer" and between 0-4 "preload shims) that are much thinner. The washers come in a set of about 10 of increasing size and the shims are used to compensate for changes in thickness of the pinion depth shim that is used to set up the gear pattern.

 

[Poser]

I am having a little trouble getting my preload correct with the pinion nut tight and wanted to make sure I wasn't overlooking something stupid.

The ring and pinion is a later style (new) that uses the crush sleeve, I am trying to use the solid spacer with shims instead. My solid spacer is approx 2.10" long with .10" in shims (all that came with the spacer) and when I try to tighten it up the preload goes through the roof. the part that is odd is the crush sleeve is approx 2.2" long and would have to "crush" to be set. So why in the heck when I start to tighten a solid spacer that is almost the same length my preload is hosed?

Just want to double check that I am not missing something before I just try to find some more shims.

thanks,
Bret

Where is your pinion depth shim located?




Between the inner pinion bearing and the pinion?


Between the inner pinion bearing race and the case?

 

[Bret]

Yes, the shim is behind the race. The vendor is going to send another shim pack but I would like to know what is different that is causing the difference. I hope to pull the outside race tonight and make sure nothing is behind it and that it is seated completely. It seems like it should be something stupid.

 

[Pin_Head]

It sounds like you are missing the thick preload washer that is shown in the Toyota FSM. You would need about 12 of the thin shims to make up for missing the preload washer. Personally, I would use the crush sleeve; just remember that you can only crush it once.
Also see:
Rebuilding and setting up a Land Cruiser differential

 

[Bret]

Does the thick preload washer fit the "crush sleeve eliminator" spacer? Based on the preload shims that came with the rebuild kit, the shims are to small to fit even at the flange side of the spacer.

With lockers and a 350 I was thinking the solid spacer may be more durable than the crush sleeve. Is this wrong?

 

[Pin_Head]

The preload washer is the same diameter as the shims, so if the shims won't fit on the pinion, the washer won't either.

There is nothing that is unreliable about crush sleeves. They are used on most modern differrentials since the 1970s and 80s including Dana 60s.

 

[Poser]

Yes, the shim is behind the race. The vendor is going to send another shim pack but I would like to know what is different that is causing the difference.

The 'difference' is the fact that the solid spacer is too short to be used with a gear set when using the pinion depth shim between the inner pinion bearing race and the housing.


If the depth shim were installed between the inner pinion bearing and the pinion, this would make the inner pinion bearing closer to the outer pinion bearing, resulting in the need for fewer shims in order to get your pinion bearing pre load set properly.



Toyota changed the location of the depth shim sometime in 1986, iirc, as there are different depth shims used from the factory with the introduction of the pinion crush sleeve and the discontinued use of the stepped pinion and spacer/shim combination.



Before I used a pile of shims on the solid spacer, I would have a machine shop make me a longer solid spacer if I did not have the means to make one myself, or use the crush sleeve.

 

[Poser]

There is nothing that is unreliable about crush sleeves. They are used on most modern differrentials since the 1970s and 80s including Dana 60s.

When used in a stock application, meaning, no larger tires, no larger engines, no deeper gearing, etc. I agree.



It is not unheard of that the increased torque that is developed with crawler boxes and other means of gear reduction prior to the pinion, to cause the crush sleeve to continue to crush. If this were not the case, why have I, and many other people who service differentials, found crush sleeves that were very loose on pinions with staked pinion nuts?

There is a reason why Marlin has been using/installing and selling these for the 8" diffs for over 10 years now.



Earlier this summer I ran into this exact issue on a V8/H55/35" tire FJ60. Rear pinion nut was tight and staked, but the pinion wobbled around inside the differential housing and ruined the ring and pinion. In the process of eating itself, it also hammered out the inner pinion bearing bore so that a race would fall into the bore and not stay put.




I am not saying you do not know what you are talking about Mr. G, as you have definitely been at this far longer than I have, and are undoubtedly more knowledgeable and experienced. I am only relaying what my experiences have been.




Oh-

The Dana 60 gear sets that I have installed have all had a stepped pinion. 4.11/4.56/4.88/5.13 ratios from Precision.

 

[Pin_Head]

why have I, and many other people who service differentials, found crush sleeves that were very loose on pinions with staked pinion nuts?

There is a reason why Marlin has been using/installing and selling these for the 8" diffs for over 10 years now.

Oh-

The Dana 60 gear sets that I have installed have all had a stepped pinion. 4.11/4.56/4.88/5.13 ratios from Precision.

My guess is that they get loose for the same reason that stepped pinions set up with shims fail. I have seen plenty of FJ40 pinions with staked nuts that are loose and they are all set up with shims.

The reason they get loose w/o the nut backing off is probably bearing wear or failure that lets the crush sleeve or shim stack start spinning and wearing.

I have more experience with old school stuff so that is the stuff I have seen fail. All the new differentials I have seen had crush sleeves. Maybe I was confusing the D60 with the GM 14 bolt, but some big beefy pinions come with crush sleeves. If there was something notoriously wrong with them, I don't think they would be so widely used.

 

[Bret]

Thank you for the insight, if the shim thing doesn't work out I won't feel bad about using the crush sleeve.

 

[CruisinGA]

Maybe I was confusing the D60 with the GM 14 bolt, but some big beefy pinions come with crush sleeves. If there was something notoriously wrong with them, I don't think they would be so widely used.

14bolt has a crush sleeve and D60 has a solid spacer/shim stack. Just helped a buddy set up one of each.

I'm about to tackle my first gear setup on my 80 series over the next couple of weeks, and was trying to decide between a solid spacer and crush sleeve. Seems to my unexperience self that the solid spacer/shim setup is a little more straightforward to install. I do have access to a lathe so I can modify solid spacers and make preload washers as necessary.