In the middle of gear swap need help!

[bluesteel1969]

I'm swapping the gears out on my 95 GT, and having the work done by a mobile mechanic. He is trying to put the new 4.10 ring and pinion in, and doesn't know the shim spacing required in front and back. Does anyone know the callout for this? Any help, or point in the right direction would be greatly appreciated.

 

[revhead347]

Well, first of all, I hope you're mechanic isn't reading this, but usually the term "mobile mechanic" is a term used to identify one who has had their employement terminated at most of the reputable shops in town. There is no pre determined number of shims. You set the pinion depth with a pinion depth tool. The pinion depth measurement is stamped on the head of the pinion gear. Shim the pinion gear until it matches that depth. Then you check the runout on the ring gear, and set it. You can do that with gear marking compound. I actually have a really good write up on it at home, but I won't be home till friday.

Kurt

 

[bluesteel1969]

Well, first of all, I hope you're mechanic isn't reading this, but usually the term "mobile mechanic" is a term used to identify one who has had their employement terminated at most of the reputable shops in town. There is no pre determined number of shims. You set the pinion depth with a pinion depth tool. The pinion depth measurement is stamped on the head of the pinion gear. Shim the pinion gear until it matches that depth. Then you check the runout on the ring gear, and set it. You can do that with gear marking compound. I actually have a really good write up on it at home, but I won't be home till friday.

Kurt

I will totally agree with you regarding the title of "mobile mechanic" and the distinct probability that they may not be reputable, although some are just doing side jobs outside the shop. Unfortunately I did not fully qualify his competence for this job prior, although I asked him if he's done gears before, and he said he had. He left my diff in pieces, and is supposed to research and ask questions, and return first thing in morning. Thanks for the info.

 

[revhead347]

Yeah, we had a notorious "mobile mechanic" in Daytona who was known for such things as leaving your transmission beside your car and then not answering his phone. He may have done gears before, but typically if you are replacing them with the same gear ratio, you can reuse the same shims, and just replace the crush washer. That doesn't work when you change gear ratios.

Kurt

 

[bluesteel1969]

Yeah, we had a notorious "mobile mechanic" in Daytona who was known for such things as leaving your transmission beside your car and then not answering his phone. He may have done gears before, but typically if you are replacing them with the same gear ratio, you can reuse the same shims, and just replace the crush washer. That doesn't work when you change gear ratios.

Kurt

I am sure that is exactly the case with this guy, he has only done stock replacement gears. If he would've glanced at the instructions that were in the box with it, he would've seen the large diagram...

 

[R.J.]

Check out these links, they will answer all of your questions.

SSOTN - Gear Install



CarTech, Inc.: Browsing Ford 8.8 Inch Differential Gear Swap



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