'08 Rear Diff Lube Change

[JohnnyO]

Changed the rear diff lube yesterday. Gen 2's have a drain plug on the diff cover which makes draining it easy. The issue comes with filling it. There is a crossmember behind the diff cover and not a lot of room between it and the fill plug. There is however a hole in the crossmember that you can stick the tubing from your suction gun through and it comes out near the fill plug. It is much easier to do this if you remove the spare tire. I know this because it's a PITA if you don't. The 5/8 tubing that came with the suction gun isn't really flexible enough so I cut a small piece off and attached a 3/8 piece of tubing inside it with Gorilla Glue. This was after attaching the 3/8 tubing to the tip of the lube bottle didn't work so well except to create a mess on the floor, my jacket, and sweatshirt. (I put a sheet of cardboard down first.)
Given the cost of three quarts of Mobil 1 75w-140 gear lube at $17 each, it really isn't worth the bother when the Valvoline Qwicky-Lube will do it for $56.95 with full syn.

There is more clearance between the front diff cover and crossmember on a Gen 2 than a Gen 1, but I couldn't get the 3/8 tubing in through the fill plug far enough to suck anything out so that is staying for now.

 

[GreenMando]

Why are you changing the rear end fluid on such a young truck?
They will easily go 100,000 miles before even considering a change.

 

[JohnnyO]

Why are you changing the rear end fluid on such a young truck?

Because I like to play. I did the transfer case last week.

 

[YeloPony]

I just got my 07 with 56k on it, and I wanted to do everything so *I* know what's in it and it's good, but after reading I don't need to bother till 100k I think I'll leave it alone.. that and the price tag for diff fluid for the front and rear...

What's your take on the ATF? wondering if I should flush that, but I hear those you pretty much never have to touch either.

 

[JohnnyO]

In the end I could have had the axle lube changed at the Valvoline Qwicky-Lube for about the same money. For the front, that's definitely the way to go.

Older models with the same driveline called for a tranny flush every 30k. That wasn't for trailer towing or anything, that was for everybody. Newer ones say 100k but if you want to keep it a while I'd do it every 30k anyway. $139 a few times for a tranny flush versus $2000+ for rebuilding the tranny is cheap insurance. The Trac has about 30,000 on it so I'll get the tranny done soon.

On the Rangers and Trac I used to have, the manual said to change the t-case lube (it's just Mercon ATF) every 60k. I first changed it years ago on the Ranger at 20k to put synthetic in (Mobil 1 ATF) and the old lube looked like tar already. Same on both Tracs.

Best part of all this? I lease a new truck every three years through my company. You never know when I'll decide to keep one though. Especially now because they're not making Sport Tracs after this year.

 

[BigV]

I was looking at my wifes 09 mariner maintenance schedule there really isn't one. Don't have to change trans, diff, transfer case fluid and fuel filter until like 100,000 or 150,000 it's crazy. I don't even think they say change the fuel filter at 150,000.

 

[JohnnyO]

Read it carefully. Most Fords, even very new ones, call for a new air and fuel filters every 30,000 miles. And don't forget the all-important cabin air filter.
(I have yet to own a Ford truck or SUV that actually had a cabin air filter.)

 

[BigV]

I checked the maintenance guide about 3 times because I couldn't believe it. I will see if I can find it on line and post it up.

 

[BigV]

I can't cut and past it's a pdf. file but every time it says to change the fuel filter it says this next to it.

Replace fuel filter (except Escape, Mariner,
F-Series [non Super Duty],
Expedition/Navigator [short wheel base only],
E-Series)

It's like the fuel filter never needs to be changed which is impossible.

 

[JohnnyO]

It's like the fuel filter never needs to be changed which is impossible.

It's possible that they have an sock-type in-tank fuel filter. My daughter's Jeep has such a unit and you don't change it unless the fuel pump craps out.
Just a guess, I don't know that for certain.

 

[BigV]

Maybe so they also don't have you change the trans fluid till 100,000 or so and the diff fluid is good till 150,000.

 

[JohnnyO]

I'm convinced that factory recommendations are only geared to get you past the warranty period.
Not flushing the tranny will get you past 36,000 miles no problem, but rare is the late-model Ford automatic (in anything they make) that will go much past 100,000 if the fluid isn't changed.
I'm working on the world record for Taurus transmission life on my wife's car. 125,000 miles so far, flushed every 25k since new. Tauri are known for weak trannys. On the other hand, something is leaking from somewhere. I just haven't figured out where yet.

 

[YeloPony]

I think the fuel filter was listed at 60k replaced on the trac.. I haven't seen anything on the tranny.