Rear gear install

[defflepp1]

So i have decided that I'm going to attempt this myself on my 03 Grand Marquis. The way i see, best case i have gears installed for around $300, worst case i have to remove the axle and take it to a shop. I already bought the diff and gears, 28 spline trac loc and 4.10 gears from an explorer. Ill also be picking up this kit to install it http://www.americanmuscle.com/frpp-88-pinion-kit-8604.html. Now i do have a couple of questions for those that have done this before

1. If i take it easy and drive responsibly do i NEED to upgrade the driveshaft? This will be going into storage for the winter and when it comes out ill probably have the driveshaft then. I just don't have access to one at the moment.

2.Obviously ill double check but, if i keep the shims straight when i pull out the old one and put them back in right, should i have any problem with backlash?
same for pinion depth?

3.Any additional advice you can give or thing i should look out for?

Any help on this would be greatly appreciated.

[RubberCtyRauder]

Not recommending this to be done as a first time I do it basis... we are talking thousandths of an inch for the proper settings for shims, gear pattern contact, crush sleeve etc. This is my opinion, but you may spend more money to et it right a second time. You need a dial indicator and knowledge to set it up right with no noise, whining, excess heat from friction of poorly mated gears. This is not a driveway bolt on operation.

[justbob]

Sometimes the shims remain the same, sometimes not. Like RCR said, you need a dial indicator plus an inch pound torque wrench to even have a clue. Not worth doing premature damage from improper set up IMO.

As for drive shaft concerns, many here will say yes but it is up to how high and how long your sustained speeds are. I never once had an issue when mine was automatic w/4.30's on the stock shaft. Many trips up to 125 and cruising at 90 for hours.


Self proclaimed Builder Of Badassery.

Buy it, Break it, Build it BETTER.
"Since 2004"

[fastblackmerc]

Spend the $300.00 and get it done RIGHT the first time. No need to upgrade the drive shaft unless you plan on doing triple digit speeds for long periods of time.

[mrjones]

Are you saying that you bought used gears out of an Explorer? If so, I'd recommend getting a new set of gears for your install. It's likely that the used gears will end up making noise when reinstalled into your MM.

[ctrlraven]

Spend the $300.00 and get it done RIGHT the first time. No need to upgrade the drive shaft unless you plan on doing triple digit speeds for long periods of time.
This^.

Used gears can be a BIG IFFY, it's recommended you install new gears. With the used diff I'd recommend having it rebuilt with the cobra clutch pak http://www.americanmuscle.com/ford-88-traclok-kit.html .

You'll also need two quarts of 75w-140 gear fluid, Royal Purple is good to use since it already has the friction modifier in it.

Replace the axle bearings/seals as well since they don't cost that much ($25-30) and everything will already be open to change them out.

Also a rear diff bearing cap stud kit is wise to get as it's just cheap insurance

The driveshaft can wait, as others have said as long as you are not doing triple digits for extended periods of time you'll be okay.

Might even be a wise idea to get a new diff cover with a drain plug,

[marauderthis]

Great learning experience if you have the right tools and someone with experience guiding you. If not... dont attempt it.


$300 is a good deal ---- if its done right

[defflepp1]

i think i should clarify, the $300 was the total cost(diff and gears) if i put them myself. i talked to a local speed shop today and they quoted about $500 to rebuild the diff and install it, and since i don't want to screw anything up i think ill just take it to them.

[fastblackmerc]

i think i should clarify, the $300 was the total cost(diff and gears) if i put them myself. i talked to a local speed shop today and they quoted about $500 to rebuild the diff and install it, and since i don't want to screw anything up i think ill just take it to them.

:up: :up:

Good deal!