Broken Gears

[jabo731]

Last week finally got to install the auburn pro diff. and new 31 spline axles. I had the ford racing 430s in there already. Left the shop drove easy for about 10 miles or so. stop at a red light and pulled off not at WOT but sort of aggressive and there it went. pop! My heart went in my mouth. Limped back to my wrench at Linco-Merc. He said that because my stock diff. was so worn on the spyder gears that my gears had probally have been weaken. He said that i had knocked a few teeth out of the pinion. He suggested that I go with the Richmond gears instead of the Ford Racing gears. What do you guys think.............

[jabo731]

at the time of installing the new axle I also had the TA girdle installed.

[TooManyFords]

I think your wrench hosed you and is blaming it on something that was not broke to begin with. When I had my Auburn installed, my friend Mike did the work and has been doing diffs for 20+ years. He told me it was important to get the pattern exactly the same when swapping just the carriers. I've got 5000+ miles on mine since the swap and it is just the same as when it went in.

No, your mechanic messed up and probably put the same shims in on each side and never checked backlash etc. When replacing a carrier you don't have to worry about the pinion shims (and he shouldn't have removed it) but you -do- have to check to make sure the ring makes the same pattern it did before. And the only way to do that, as Mike taught me, was to check the pattern before disassembly so you know exactly what it was. With that you can then match the new carrier assembly to this pattern by adjusting the shims on each side.

Those gears were already broke in and mated and had he done his job correctly, you should have been able to drive it like you stole it after leaving.

Now, how you go about getting him to admit his mistake is probably going to be tricky... You did keep the old carrier, right? Worn spyders or not, they don't control how the ring and pinion gears mesh. if you didn't hear the gears whining before then you should be able to conclude that they were setup correctly the last time.

I'm sorry to hear about the problem. I hope they do right and fix it under their dime.

John

[jabo731]

Thanks TMF I'll see what happens tomorrow. So the Richmonds are no better than the fmc and as you stated probally had nothing to do with the failure.

[SergntMac]

Thanks TMF I'll see what happens tomorrow. So the Richmonds are no better than the fmc and as you stated probally had nothing to do with the failure.I agree with John (TooManyFords) 100 percent. The first set of gears in the #1x were Richmond, and they got trashed at 16,500 mile when 3 ring bolts came out. Junk.

I replaced them with Ford Racing gears in 2003, and added 25K miles of brutal punishment, later overhauling the rear end last November to upgrade to 31 spline Moser axles and Auburn Pro diff. Gears looked great, reused them, and set up the rear end exactly like John said.

BTW, get the girdle and stud kit, you shouldn't be running around without them, IMHO.

[jabo731]

I picked up my car today from the wrench. The Richmonds seem to have a slight whine at a coast. Richmond recommends driving 10 miles and cooling down for 30 minutes 3X. Hope all holds up.

[TooManyFords]

As long as you don't hear any whine while power is applied then this could be considered as normal.

My first setup of the 4.30's had this and nothing bad. When I had my diff swapped the second setup eliminated it. My wrench is good!

:D

John

[jabo731]

This is a brand new diff. and 31 spline axles so I assume everything has to break in.

[Dennis Reinhart]

Last week finally got to install the auburn pro diff. and new 31 spline axles. I had the ford racing 430s in there already. Left the shop drove easy for about 10 miles or so. stop at a red light and pulled off not at WOT but sort of aggressive and there it went. pop! My heart went in my mouth. Limped back to my wrench at Linco-Merc. He said that because my stock diff. was so worn on the spyder gears that my gears had probally have been weaken. He said that i had knocked a few teeth out of the pinion. He suggested that I go with the Richmond gears instead of the Ford Racing gears. What do you guys think.............

I think he is WRONG on Richmond gears and I would suspect a improper install

[BlownBlass]

I believe your wrench did not do the proper job and this caused the failure. It has been my experience that Richmond gears are a bit on the noisy side however Richmond does make a Pro line aptly named Richmond Pro that is as quite as the FR gears and in my opinion stronger. I have used Richmond gears mated with moser axles in some very powerful cars like my Malibu and never had a problem.However with my MM I will choose FR 4:30 gears as they are reasonably priced and I am not on the high power end.

[BUCKWHEAT]

I had your problem but in a different order. I trashed the FMS 4:30 pinion, and then put in the 31 splines, Auburn and a new set of 4:30's from FMS. All is fine. My son has Richmonds in a GM A body behind a 389 Poncho. They whine.