Hey guys, as you may or may not know my rear diff has a leak. Before I just swap out the fluid and bolt it back up I want to go ahead and replace my axle bearings & seals so I won't have to forgo all the $$ I spent on the gear oil if I have a bearing or seal go out. Make sense? Clear as mud?

Quitin did an excellent article on his 04.

https://www.f150online.com/forums/ar...lots-pics.html

I'm wanting to to this with his post as a guide on my 2003.

My question is WHY MOTORCRAFT? I'm trying to save a few $$$ as everyone is in this economy. Will Timken or any other brand work just as well? I understand that the MCs will work flawlessly as they are a designed OEM part. I can't even find out what MC part numbers MY truck takes---local ford dealer says they changed mid year and it could be either 1 of 2. So I may have to buy both so I have the parts on hand and compare on the disassembly. Which also confuses me when I look at non-MC parts as to which ones to get. Any advice?

Sidenote question---Forgive my ignorance, but what is a "wet clutch application" for rear ends. I picked up a bottle of gear oil that said NOT to be used in wet clutch applications.

Thanks--DirtySCREW

 

They probably did change mid year. All you have to do is give your dealer parts department the VIN of your truck and they'll tell you exactly what ones are used in yours.

I would use motorcraft if I where you. but I dont see why an aftermarket company wouldnt work just as good

 

I went with Quaker State 75W140 which is a full synth for both axles and added a bottle of FM for the rear since I have a LS and didn't have any problems with it ever. Basically you can use any brand of oil as long as you use one that has the same specs as per recommend by the car company.

 

And as for seals+bearings (forgot to answer that one). Pretty much every company will work. The question is do you want peace of mind. As for seals price will vary upon the materials it's made from this will determine how well they are going to hold up to your operating environment and bearings price will vary with the precision of the inner/outer races and roller *****. So what you need to know if you want to go the cheaper way is in what kind of environment your truck is operated (ex: towing, extreme heat, sand, daily driver, how long do you plan on keeping it for) from there choice is yours: motorcraft will hold up to pretty much everything while still being reasonably priced compared to higher end company's that are made for extreme use and timken could be just fine for you if don't plan to ''trash'' your truck around.

 

Drick----I DID give the dealer my VIN!! He said his computer showed TWO different bearings and TWO different seals for an 03 with the 9.75 rear end. This is my luck. I'm figuring I have the more expensive ones--again...my luck.

I plan on keeping my truck a long while and want her to last. I'm leaning toward "doing it right" and staying with the MCs; if I can find the right part numbers. I wish I could so I could go online and compare prices from my dealer and a reputable online source with shipping.

I'm gonna go with Royal Purple gear oil, 75w140 rear and 75w90 front diff. I'll have to double check but I'm sure it meets or exceeds Ford specs.---DirtySCREW

 

Finally---I got the MC part numbers. Funny thing is my local dealer is OVERCHARGING for them. I called another dealer about 20 miles away, and they are selling the bearings for $7 bucks cheaper and the seals .86 cents cheaper.--That's $15.72 cheaper!!!!

Where can I go online to find/order MC parts where i may be able to save even more??

For those of you with 2003, 9.75 rear end Limited slips here are the part numbers:

Bearings: 5L3z 1225 AA-----$67.53 each (ford retail)

Seals: E3TZ1S77A-----$6.60 each (ford retail)

The above prices are from the dealer that's 20 miles away.

------------DirtySCREW

 

Seals are $4.50 at rockauto.com. It doesn't look like they carry the bearings.

For discounted OEM parts, contact Domenic at Tasca Ford.

www.tascaparts.com

 

Yep can't go wrong with Tasca parts. And you can be sure that what they will send you will be a direct replacement for your truck. If not they will take the part back and send you the correct one at their expense.

 

Thanks Glc.....i was thinking I might have to recant what I said earlier...as I've foud Timken bearings at Autozone for $30.99!! I could get both bearings and both seals for the price of ONE MC bearing!
Timken part numbers for those that are interested:
TF01561R---bearing--$30.99 Autozone online
100357------seal---$6.99 Autozone online

I will definitely have to check out Tasca. Thanks again guys; ya'll are great---DirtySCREW

 

hey guys, need to confirm the rear diff capacity. Quitin said 4 qts on his write up. On the owners manual I downloaded from the ford fleet website it says "2.6L (5.5 pints)" for the 8.8 and 9.75 rear end. Going by this and converting pints to quarts its only 2.75 qts. Is this correct? Did Quintin have the 10 inch rear end?---DirtySCREW

 

Differential, Ford 9.75 Ring Gear Rear..........5.5 pints

Limited Slip Differential, Rear......GL-5
All TEMPS......75W-140
Synthetic oil is required.
Add 4 oz of friction modifier part no. C8AZ-19B546A
(EST-M2C118-A) or equivalent)

 

If the seals are not leaking why change them? A wet clutch is submersed in oil. A dry clutch is not.

.

 

JMC---my rear diff cover is leaking. I'm going to replace the seal and also fresh gear oil---probably Royal Purple 75w140. I don't want to go through the expense of the gear oil to have a bearing or seal go out later on. I have 141K miles on my truck and after I do the bearing, seal and gear oil change I'll be set for the rest of the life I own the truck.

GLC--you are correct on the 5.5 pints; that converts to 2.75 quarts. Did Quitin just want some extra or did he have a 10" rear end that required the extra 1.25 quarts?

I went ahead and bit the bullet and ordered MC parts from Tasca. (Thanks again GLC). Thye were about $30 bucks more than the non-MC ones at Autozone, and for $30 I'd rather have the peace of mind. I just hope I get the correct parts!!---DirtySCREW

 

Bearings and seals can last for hundreds of thousands of miles like they can let go in 10K. My credo is if it ain't broke don't fix it. So then I am of the opinion that it doesn't make sense to do the extra work.

.

 

JMC--I can agree with you to an extent; however I do have some type of noise coming from my passenger rear. I think (from reading on here and on other forums) that that bearing may be going out or is out...kinda like some parasitic drag sound...and it aint the ebrake. I guess more than anything its for peace of mind. I'm trying to gain (however slight) performance and mileage as well. Hopefully after this, I can save up for headers and Troyer E-fans.----DirtySCREW