Gear Questions?

ceracer33 said:

i will be doing a gear swap soon more than likely and would also like to know if there is a write up on how to do it. unlike him i do not have anyone willing to do it for me so im stuck doing it myself.

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gtstangau said:

Yeah I will probabbly get that guy to put them in for me! Is a rebuilt LSD locker as good as a if I were to buy a brand new Eaton locker?

An I have 115,000 miles on the ol stang so I already got the new bearing kit! Ahhh I can't wait man I have heard everybody talk about how awesome gears are im ready to get them in!!!

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gtstangau said:

Yeah I will probabbly get that guy to put them in for me! Is a rebuilt LSD locker as good as a if I were to buy a brand new Eaton locker?

An I have 115,000 miles on the ol stang so I already got the new bearing kit! Ahhh I can't wait man I have heard everybody talk about how awesome gears are im ready to get them in!!!

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gtstangau said:

What kind of gear oil should I use? How much does that usualy cost?

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03ghoststang said:

Well this will be my second write up, but this one will be on gears. Key note this was on a 5.0L but same principles apply to a newer mustang with a 8.8 rear end the only difference is the disc portion and abs sensor. but i will note what is needed for that also. I took a total of 4Hrs to do patienece is a key thing here..

First of on tools needed: (*some are special tools*)

I might of mentioned other tools i used during the install not mentioned hereon the list

1) if available impact gun other wise a 1/2 breaker bar or ratchet

2a.) socket in 1/4in. drive 8mm only
b.) socket(s) in 3/8in. drive 12mm 12pt., 13mm, 15mm, 19mm
c.) sockets in 1/2in. drive 19mm, 1 1/16in.

3a.)1/4in., 3/8in., 1/2in. ratchet
b) 3/8in swivel

4) wrenches 8mm, 13mm,

5) E8 female torx for the ABS sensor located in the back of the rear disc

6) *magnetic base indicator* , *0-6" digital caliper*, *press* * in/lbs TQ wrench*

7) pry bars different sizes, punch

Ok now here we go on to the install gears and fluid used where FRPP 3.73's and Royal purple diff fluid caomes with friction addetive


First of I used a craftsman professional jack to raise the car, and had some decent size jack satnds to make the room neccessary to clear for the install. Removed both rear wheels to be able to remove C- clip later on in the process.
See pic



Now i removed the bolts with a 13mm short and deep socket on the rear diff cover except for the top bolt just loosened it up a bit. I use a screwdriver to pry the cover open slowly to release the fluid so it wouldn't get all over the place, now you will need a pan that can hold at least 3qts., then once all fluid is drained remove the top bolt.You can see what i mean in the pic below.



For the mustangs that have a rear disc set up you will need teh 13mm wrench to remove the top part of teh caliper once that is removed a 15mm wrenchor socket with ratchet to remove the bottom portion to be able to remove the disc. No pic shown... sorry

Now that the rear Diff cover is off you will need the 8mm wrench to remove the shaft locking bolt. Shown in pic


after you will need to rotate the carrier about 180* for the shaft to slide out. After this you will push in the half shafts to remove the C-clips and the slide the shafts out slowly so not to damage the seal. A 19mm socket will be needed to remove the cap screws on the carrier caps. They are tight so i would recommend using a 1/2 in. ratchet with long handle to break them loose.Important note everything that is removed must go back to the same spot and mark the caps left and right. You dont want to mix these up. Once that is out the way you will need a pry bar to push teh carrier up for it to pop out * Be careful this thing is heavy * the races will come out along with the carrier.



With the carrier removed you will now take the drive shaft out there are holes there to put a punch in to lock it in place to be able to remove the bolts. Important these bolts are 12pt. so only a 12pt. socket will be needed. Once the drive shaft is removed the bolt that holds the pinion is a 1 1/16in. you can use the 1/2 in. ratchet but i chose my impact gun. Once the that is removed you will need a hammer preferably a rubber mallot to push the pinion out here is where things get tricky for those that dont really know how to do it.

Here you will need a bearing puller to remove the bearing on the pinion, once the bearing is removed you will have the shim that goes with that. i used the MHD setup for the shimming process. I had asked a trusty friend of mine also about this and most of the time you can use the same shim form the old one on to the new one, but to make sure i used my 0-6" digital caliper to measure this and i got 1.908 on the old one with the shim i put that shim on the new pinion and measured got the same thing. Just incase you get something different use the shims that come in the kit to get the measurement form the old pinion. Now you will need a press to press the bearing on the new pinion i had one so it was easy.




After all that i reinstalled the pinion with new crush aleeve and tighten the new nut down here is whre you will need a in/lbs TQ wrench another special tool to get the proper rotational TQ or drag on the pinion. All specs will be written in the end.



Now onto the carrier a vice will be required to remove the bolts to replace the ring gear. After teh bolts have been removed a couple of taps fromt teh hammer will be needed to pop it loose. Now you can remove the carrier to slip the new ring gear on, once that is done you will bolt up the ring gear to the carrier first do 5 bolts in a star pattern to seat it then bolt the rest and use lock tight on those bolts they will be TQ to 70-85 ft./lbs.

After that reinstall the carrier along with the races. Here comes the most time consuming and where patience is really put to the test for a first timer... because you will need to put the carrier shims back now this is the key part on install, they are tricky to put back but it's doable now i did all new bearings and races so the kit came with new shims i had to use those since the ones that came out wouldn't give me proper backlash. Here is where the back lash part come into affect i tighten teh bolts down just snug and checked back lash until i got it right, and i had to add and subtract shims this took me about an hour to get right. This part will make the difference in a good install or a bad one. Here is a pic


So once i got that done and it was correct i TQ the caps down to 70-85 ft/lbs. and also checked the wear pattern and it was dead on after this i put everything back together, put the drive shaft, cover and filled with fluid...

Well this install took me about 4Hrs but the payoff is great now i took it on a road test no whines or noises ..


TQ specs took these from my friend:

pinion preload = 8-14 in/lbs (used bearings)
pinion preload = 16-25 in/lbs (new bearings)

ring gear bolts = 70-80 ft /lbs
bearing cap bolts = 75-85ft/lbs
pinion shaft bolt = 10-15ft/lbs
drive shat bolts = 85-95ft/lbs

back lash .008-.015" try to get it around .010-.012"

well thats my write up on how i did the install. Another key note it will be easy if you do have mechanical skills and the tools required for this job otherwise just pay for the install to be done by a profesional or you will be sorry...

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fast97gt said:

borrowed this from newbies list at the top of this forum page.

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gtstangau said:

Thanks for the write up man, I will probablly get that guy to install them for me scince I don't have the special tools!

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fobra559 said:

I remember this thread when I got my gears. Nice write up man

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