differential setup - hard to find shop - ez to do

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took apart a ford 9" differential to install a locker. got lazy and tried to find a shop to set it up. first place I called was an axle shop that was recommended plus they did some Jeep work for me in the past. no dice. they didn't wanna touch it. tried two more shops. nobody wanted to touch it. fine. my 13 year old and I started through the process: backlash, preload, we checked the pattern: coast was perfect, drive side was low and too much to the heel. my 13 yo son finished it today by himself;

so.... If a 13 year old can do it, why don't shops wanna touch it?
 
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They don't want to be responsible for something that you could mess up after it left their shop.
 
Originally Posted By: simple_gifts
I don't know any place that wants to finish someones else's unfinished job
'Zactly my thought.
 
It would not have been an unfinished job. they would have gotten a complete 3rd member/carrier with all of the pieces in it. they could have replaced the bearings and done a complete rebuild. 3 bearings and all of the setup. how is this any different than removing a transmission or an engine and taking it for a rebuild.
 
It's not installed in the vehicle yet? I wouldn't declare success just yet.

I would have done it for you, 9" Fords are easy & I'm very familiar with them.

I only warranty against gear noise if NEW OEM or Yukon Ring & Pinion set are used, No warranty on overheated gear sets from incorrect break-in/overloading/fluid level, No warranty from damage caused by contaminates that came from the differential axle housing on carry in 9" center sections (not my fault the housing in your car has a pound of metal shavings in it), Last but not least.....No warranty on customer supplied parts.

If I build the differential from scratch, Buy the parts, Install it, Break it in.....I give a 2 year unlimited mileage parts/labor/noise warranty (minus the gear oil).
 
Originally Posted By: tomcat27
It would not have been an unfinished job. they would have gotten a complete 3rd member/carrier with all of the pieces in it. they could have replaced the bearings and done a complete rebuild. 3 bearings and all of the setup. how is this any different than removing a transmission or an engine and taking it for a rebuild.


5 Bearings in a 9" center section.
 
sounds good to me! all new parts that you source? fine! Yukon gears and locker? fine! I'm not looking to save pennies here - almost everything else on the car is new and improved: engine, transmission, wilwood brakes, suspension, all accessories. there's only 2 parts under the hood that are original: the distributor hold down, and the oil pressure sensor adapter. only thing left after the rear end is steering.
 
Originally Posted By: clinebarger
Originally Posted By: tomcat27
It would not have been an unfinished job. they would have gotten a complete 3rd member/carrier with all of the pieces in it. they could have replaced the bearings and done a complete rebuild. 3 bearings and all of the setup. how is this any different than removing a transmission or an engine and taking it for a rebuild.


5 Bearings in a 9" center section.


I never said that I could count.
 
Originally Posted By: AVB
They don't want to be responsible for something that you could mess up after it left their shop.


Yep, he would've got turned around at my door too. He's already complaining.
 
Race shops will do it, at Race Shop labour charges, which can be less than ordinary car shops but at worst, no more. Talk to the racers in your area and they will put you on the right guys.
 
Don't know if it's still around but we had not far away a dedicated differential shop.
Although back then they generally didn't accept customers bringing in parts to use.
Another shop up the hill would do complete rear & front ends mainly for the off road crowd. Had complete units lined up on the floor all clean & pretty ready to go out the door. Just no mounted wheels/tires on them.
 
What type of locker?

Full carrier locker or a detroit/spartan/aussie auto locker?

I'd check if there are any off road shops. Any off road shop should know their way around differentials.
 
It's hard to find good shops that aren't just parts swappers. They are used to someone coming in with a blown up rear axle that they can just swap a junkyard axle with. Much easier to do and can still charge a bunch of money. There are a few really good professional shops around here, and they are constantly busy for that reason. I agree with Miller88 that your best bet would have been an offroad shop.
 
It's time consuming to do a setup correctly. Lots of other quicker jobs to make money on. Even setup correctly it may have noise. Most shops don't want the potential hassle.
 
Originally Posted By: clinebarger
It's not installed in the vehicle yet? I wouldn't declare success just yet.

I would have done it for you, 9" Fords are easy & I'm very familiar with them.

I only warranty against gear noise if NEW OEM or Yukon Ring & Pinion set are used, No warranty on overheated gear sets from incorrect break-in/overloading/fluid level, No warranty from damage caused by contaminates that came from the differential axle housing on carry in 9" center sections (not my fault the housing in your car has a pound of metal shavings in it), Last but not least.....No warranty on customer supplied parts.

If I build the differential from scratch, Buy the parts, Install it, Break it in.....I give a 2 year unlimited mileage parts/labor/noise warranty (minus the gear oil).



How do you break it in?
 
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Everybody has different break-in procedures.....This is mine.

*First I run the vehicle on the lift with the wheels off the ground for about 15 minutes to distribute the gear oil.
*Drive the vehicle lightly for about a mile, Keeping it under 45mph, Let the diff completely cool down.
*Drive the vehicle lightly for about 5 miles, Keeping it under 55mph, Varying speed as much as possible, Let the diff completely cool down.
*Drive the vehicle lightly for 10 miles, Keeping it under 65mph, Vary the speed, I usually do this on the drive home as I live exactly 10 miles away from work.
*I drive it to work after sitting all night, Drop the "Bulk" 80w90 out, Check the Back-Lash & Inspect the gears. Fill the diff with a quality synthetic gear oil, I use Delvac 1 if the customer doesn't have a preference.
*Instruct the customer to NOT beat on the diff for at least 100 miles, Keep the speed resonable, Vary the speed as much as possible.....A lot of people don't listen, Some do "John Force" burnouts right in front of the shop.

This is mostly do to me setting-up diffs on the tight side of the printed specifications, Overheating the gear set/gear oil is very easy to do in the first few miles.
 
Years ago, I needed a 10 bolt built for an 80 F body. The trans shop that I still use today gave me a price and I trust their work 100% gave me a price. I don't remember what it was but it was reasonable for the time.
Anyway, I was a diesel mechanic at the time and could build injection pumps and do complete overhauls on engines so why not do my own diff?
I bit the bullet and bought a T&D pinion depth measuring tool. I built the whole thing with all new bearings, Richmond 3.55:1 gears and a Strange posi carrier. Rearend is still in use today. I probably built it 22 years ago.
I used the same logic for bicycle wheels and now have a nice little side business doing that.
Anyway, it isn't alchemy or black magic. If you guys set it up right, you set it up right. The break in instructions Clinebarger posted are right on.
BTW, that T&D tool was pricey but it's paid for itself over and over. it's done a bunch of diffs.
 
I've set up a good number of ring and pinion gearsets over the years. I don't find it difficult. There seems to be a stigma involved with it.

Most recently, I changed from a 4.10 to a 3.63 in my Turbo S2000. I used new gears, had the gears cryotreated (maybe worthless but did it anyway) purchased solid pinion spacers (not the crush kind) and set about to assemble it correctly.

It was not particularly difficult to set the pinion depth correctly, with a little bit of trial, measurement and adjustment. Then getting the backlash correct was a simple matter. Works perfectly!
 
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