Diff Fluid, Trans Pan, warm-up times, etc?

[Todd82TA]

Hey guys,

My 2002 has about 48k miles on it right now. It's 9 years old now, and as far as I can tell, the differential fluid is original. The transmission fluid is also very clean, but I think it might be original. Even at 48k miles, it's probably best to change it every 35k so I think I'm going to do it now.

I've got a couple of questions:

1 - For the differential fluid, how do I know how much to put in, and what is the best fluid. I'm thinking of just getting something from Royal Purple or Redline. It's a NON-POSI unit, so I don't really have to worry about any of that, I just want to give it the least amount of friction as possible and hope that improves the fuel economy and life somewhat.


2 - For the transmission fluid, can anyone recommend a good aftermarket transmission pan that will give me additional capacity, but that also has a drain-hole? What fluid do you guys recommend? I used Redline ATF in my Crown Victoria, and ever since then, the shifts seem to have gotten smoother (which means it's not working as well as the old original Ford fluid did).


3 - As far as the transmission goes, is there a warm-up period for the transmission to reach regular operating temperatures? I'm just curious because I tend to beat the piss out of my cars as soon as the engine has warmed up, but now I understand that for automatics, it can sometimes be a bad thing to beat on them until the fluid has warmed up as well...


Just saw the comment about John Rock. I never knew the guy, but my condolences to everyone on here.


Thanks guys,

Todd

 

[1AJeremyD]

So yo give you a small a mount of insight into everything

1-You should fill it up till its justs pouring out of the fill hole. Royal purple is expensive and will do the same thing as any other synthetic rear diff fluid.

2-If you are looking for a better way to cool your transmission down then I suggest getting a transmission cooler. More fluid really doesn't make the difference, it's heat transfer. There are a couple of people here that can help you out with that. I would just go with regular Mercron V for the fluid.

3- Really the only way to warm up a transmission is to drive it. Same goes with the differential. Theres no combustion going on in there so they both rely on friction to get up to temperature.

 

[Todd82TA]

So yo give you a small a mount of insight into everything

1-You should fill it up till its justs pouring out of the fill hole. Royal purple is expensive and will do the same thing as any other synthetic rear diff fluid.

2-If you are looking for a better way to cool your transmission down then I suggest getting a transmission cooler. More fluid really doesn't make the difference, it's heat transfer. There are a couple of people here that can help you out with that. I would just go with regular Mercron V for the fluid.

3- Really the only way to warm up a transmission is to drive it. Same goes with the differential. Theres no combustion going on in there so they both rely on friction to get up to temperature.

Thanks Jimmy! I really appreciate it. Having the pan with more capacity had several benefits (that I could forsee):

1 - It would come with a drain pan so I could change it out more frequently.
2 - It would keep the transmission cooler.
3 - The extra fluid would mean that it wouldn't get dirty as fast, and would therefore extend the life of the transmission.

I figured since I was going to take the pan off anyway, might be nice to get a newer pan while I'm under there. But if you think it might actually hurt the reliability of my transmission (as in, the tranny doesn't warm up quick enough), then I won't bother.


Thanks!!!

 

[JohnnyO]

The rear diff holds about 1.5 quarts. For the tranny you are better off going to a dealer or shop that has a flush machine to change out all the fluid. Dropping the pan only gets about one-third of it. The tranny is a 5R55E, check Summit, Jeg's, B&M, for a new pan. The manual for your truck calls for a tranny flush every 30,000 miles.

 

[Todd82TA]

The rear diff holds about 1.5 quarts. For the tranny you are better off going to a dealer or shop that has a flush machine to change out all the fluid. Dropping the pan only gets about one-third of it. The tranny is a 5R55E, check Summit, Jeg's, B&M, for a new pan. The manual for your truck calls for a tranny flush every 30,000 miles.

Thanks Johnny, I appreciate it.

I just looked around, and the pans are pretty expensive. I've got a trans-pan oil plug kit that I had intended to install in my own, but I discovered that the transmission pan in the 4x4 5R55E has ever so slightly more capacity, but more importantly, has a little flat spot next to the recessed area that I can install a drain plug into. So I ordered one off eBay for $20 bucks. I'll paint it, install my drain plug, and I should be good to go.


Thanks!

 

[sickwilly]

These STs come with a transmission cooler. Are you suggesting a larger one?

I have been eying an aluminum one on ebay, but did not pull the trigger when I dropped my pan. Instead I opted for a moeller vacuum extraction fluid vac.

I will tell you, I dropped my pan at 55K, and even though my fluid was so new and clean you could reuse it, changing out the filter really seemed to improve the feel of the tranny -- not that I though there was any problem to begin with.

I just use any auto store brand Mercon 5 since I change out 3-4 quarts every other couple of oil changes.

 

[sjr033]

The rear diff holds about 1.5 quarts.

I think you mean about 2.5 quarts

 

[1AJeremyD]

These STs come with a transmission cooler. Are you suggesting a larger one?

Ya installing a larger cooler will always help out. Keeps things cooler and from overheating

 

[Fredness]

Linkage!
This should answer a bunch of your questions.
PML makes the deep pan for the 5R55E - VERY nice and I'm really happy with it.

Since you have a 4x2, you can pick up an extra 1/2 to 1 quart with a 4x4 pan - it gives you a deep sump to draw from to prevent running dry on turns, angles, acceleration and stopping. I have one ready for a drain plug (removed for this install) that I can let go dirt cheap - just add a 4x4 filter and you're set.