Need help with this pattern - pics inside
I don't think you need them for this job but if you need some thinner shims, .003, .007,.010 for the next job, PM me with your address and I will mail you some.
Backlash for that last setup was I think 0.006-0.007. I'll try to get it a bit bigger tomorrow morning.
And I am not really planning for the next job really soon - hopefully this setup will last as long as I will have this car

Yeah another question I had 3.23 gears and this is 3.42 I am installing. Should I reprogram computer for that? This is V6 manual transmission
That seems to be the recommended amount. .006-.008 backlash is usually what I see quoted. I even saw one for .010.
With that being said, TREX is right. The Ratech kit's lowest increment is .011 on the carrier shims. Called up Randy's ring and pinion and got a "locker" shim pack with shims in the .0065 range and a lot of .0075's. A GREAT variety of them too, not only that it was easy to install with the "lock" portion of the shim pack.
That seems to be the recommended amount. .006-.008 backlash is usually what I see quoted. I even saw one for .010.
You are correct on the spec for the backlash, but I use that for a target only. The same thing with the pinion depth measurement. Alot of times I need to "cheat" the specs to get an ideal pattern. Bird's pattern, the best I can see should be fine like he has it but it looks like a few thousands more BL may get it cleaner. It may not, just try and see.
This week I had some 2 cut gear from .0025 to .010 and Ford 8.8 that spec at .012 end up setting them at .008 to get a clean pattern. Use the spec to get close and let the pattern give you the final answer.
Also the only thing you have to watch for on some of the selectable interlocking shim packs is sometimes the thickness varies alot on the outer thick part of the shim pack. They look like they are ground on an angle and the thickness will vary .006 or more. I have not had many like it lately but measure it in several places just to be sure when you use them.
I know I got off topic but I thought this may help.
Later
The Best V8 Stories One Small Block at Time
My 115psi 8Gal compressor with 500 ft/lbs goodyear impact wrench didn't work there
But common - it worked - but I think I overtighten that nut a little - it is about 35-40 in/lbs now - do you think it is gonna be a problem?
Thanks for your help guys - you are alsome!
got to go to work now - will finish on weekend
Later
I was trying to get 0.008 - but when I got 0.007 I thought it would be allright too - didn't wanna mess with it nomore - I had enough
You might find that it is a little noisy with .007 lash, but it certainly won't be detrimental to the gear life. However, being that it is a V6, I don't think you need that tight a lash for good life. You could probably open it up to .010 and be fine.
As far as the preload, that torque wrench looks awfully big to be reading in in-lbs, is that a ft-lb torque wrench ? Your pinion bearing preload if it is new bearings should only be about 20-30 inchlbs, not ft lbs. If it is a in-lb wrench, then even at 35-40 you are a little tight, it will cause your pinion bearing to run hot, might even cause it to fail (although 35-40 isn't that much too tight). You might be able to get away with it, but I would probably loosen it a little.
Just my .02...
You are correct on the spec for the backlash, but I use that for a target only. The same thing with the pinion depth measurement. Alot of times I need to "cheat" the specs to get an ideal pattern. Bird's pattern, the best I can see should be fine like he has it but it looks like a few thousands more BL may get it cleaner. It may not, just try and see.
This week I had some 2 cut gear from .0025 to .010 and Ford 8.8 that spec at .012 end up setting them at .008 to get a clean pattern. Use the spec to get close and let the pattern give you the final answer.
We were talking about the pinion shims earlier not the carrier. I have a bunch of the selectable "super shims" in stock that you are talking about with the thinner shims from .005 to .008 which do make life easier. Although you really do not need anything less than a .010-.012 on the carrier to get it where you want as long as you have a good selection. .011,.013,.015-and up.
Also the only thing you have to watch for on some of the selectable interlocking shim packs is sometimes the thickness varies alot on the outer thick part of the shim pack. They look like they are ground on an angle and the thickness will vary .006 or more. I have not had many like it lately but measure it in several places just to be sure when you use them.
I know I got off topic but I thought this may help.
Later
Going to tear into mine again, given your guys responses I'm going to loosen up backlash and check the gear pattern. I'll post up with pics. They are a whining quite a bit on decel and it gets louder on hard right turns.
They were VERY quiet when I first set them up. I had to replace the diff. because it was going out and I can't seem to get them right again.

Question, what kind of preload do you guys put on the carrier? What rule of thumb do you guys use?
Am I correct on this, because this is what I have been doing.
I was trying to get 0.008 - but when I got 0.007 I thought it would be allright too - didn't wanna mess with it nomore - I had enough

That right there is the main thing when setting up a rear. Patience
, you are so close, don't give up now.And the coast side is where alot of your pattern info comes from. That is what I was going off of on suggesting you loosen it up a little.
Am I correct on this, because this is what I have been doing.
And if you are working with a used set of gears, pay more attention to the coast side and try to put them back where they had been running. I mean checking the lash before pulling them out will save you alot of headache. When you reinstall shoot for the same number that they were running at, forget the specs or suggested backlash. And don't let it scare you if they are up there around .012-.015 or so.
Once again let the pattern, especially the coast side give you the final answer.
Last edited by DynoDR; Feb 3, 2006 at 09:16 PM.
The one in your picture looks like a click type Ft-lbs wrench. ?
My 115psi 8Gal compressor with 500 ft/lbs goodyear impact wrench didn't work there
But common - it worked - but I think I overtighten that nut a little - it is about 35-40 in/lbs now - do you think it is gonna be a problem?
Thanks for your help guys - you are alsome!
got to go to work now - will finish on weekend
Later
I got the new pinion bearings today and pinion shims. I'll be tearing into it tommorow.
Edit: Question, why are you emphasising (sp?) the coast side vs the drive side?
When I was setting up the gears I got the coast side perfectly, at least it looked like to me. The pattern was centered on the gear and had a nice symmetrical oval shape, BUT the drive side looked biased towards the inner portion of the ring. I didn't quite know how to interpret it so I decided to center the drive side and the the coast fall where it may. Input?
Last edited by sscam68; Feb 3, 2006 at 10:33 PM.
The one in your picture looks like a click type Ft-lbs wrench. ?
Should I get the new pinion nut too, or the one I'm using will be okay?
And like I said before I used that click type ft/lbs wrench and my carjack to push it just to turn that nut - I have SnapOn dial type in/lbs wrench to check preload (borrowed from a friend of mine)


