I'm replacing the trans on my E350 (351, E4OD) this weekend. Got the old trans out and I'm about ready to put in the new one. (Reman from , 3 year warranty. $1000 core charge!! )

My front main seal is in pretty bad shape, but I need to leave that for another day. I'm sicker'n a dog, as is my main helper, #1 son. But the trans replacement has gotta get done, so....

Dunno about the oil pan gasket, as there's so much oil from the front that I can't tell. Same for the rear - I really can't tell what shape it's in.

But with 188k on the clock, it's a good bet that the RMS could stand to be replaced.

Any info on how big a job it is would be appreciated, as we all any tips on making it easier.

With the trans out, should I consider doing the oil pan, or is that not going to make much of a difference?

 

Replaced my steering box with a FoMoCo rebuilt part, my cost: $258, core $275!! I made damn sure that core was back at the dealer within the week, even cleaned it up and made sure the return box was perfect too!

Were it me I'd change the RMS but not sure about the pan unless its much easier than I'm thinking it might be doing that in a van. I've not seen too many oil pans leaking but since the front seal has issues its tough to tell at this point I'm sure.

There's no better time to service the RMS than now for you---doing it later means R&R'ing the trans one more time. For the $50 or less for that seal it doesn't seem worth the gamble.

 

hey Wireless,
It is a wise thing indeed to be replacing the rear main seal with the trans out. That particular one is a one piece seal that comes straight out the back, one of Ford's much highly well thought out designs. It can be done quite well and easily without all of the recommended specialty installation tools. I've probably replaced at least 12 of them. The oil pan gasket is another thing entirely. It's do-able but plan a day and some cursing to go with it. I have not wanted to ever do an oil pan gasket unless the engine was out of the vehicle. The front main seal is more common for needing replacement (in my experience) and if you're lucky, could be the source of your oil leak. And I don't blame you for wanting to leave that one for another day either!!

 

Well, that was easy! It's a 10 minute job for a newbie. Once the trans is out, of course.

The RMS, that is, not the trans!


Got under there and found my rear heater lines were badly corroded and leaking, so off to the parts store for some 5/8" heater hose, and got that done. I used a reciprocating saw to cut the pipe before it went up into the engine compartment, to get it out of the way. In retrospect, I should have cut it just below where it changes to hose, since the pipe is solidly mounted and would have provided a good mounting point to keep the new heater hose off the engine. I'll have to fab something for that.

It really wasn't a bad job with the trans removed, but it could be done with it in. There would be a bit more fishing, but it's very doable.

So on to the trans itself:

My jack stands aren't tall enough for the trans to slide under the van while mounted on the transmission jack (a nice pro model rented from the local Sunbelt place.) Soooooo, we had to put the jack under the van, and muscle the trans under the van, and then muscle the trans onto the jack. Some ingenuity, a 20,000 ratcheting cargo strap run over a cross member, and a little hoisting with another cargo strap up through the doghouse, and we got it done. Not easy, especially when my best helper and I are both sick.

So, this morning we plan to get the trans back in and hooked up. That will require some creativity, too.

The warranty requires a few things:

1. Replace the existing external trans cooler.
2. Add another external trans cooler.
3. Add an external fluid filter.

With these things done, it's a 3 year warranty. Otherwise, only one year.

For the filter base I bought one from B&M that came with a dinky filter that's about the size of the trans filter on later models. Smaller than a Coke can. But, the base will take the same size filter as the engine, which will keep my filter inventory simple. It's also major overkill, which I like. More flow is better!

I found a good place to mount it to a cross member just ahead of the gas tank. I've fabbed a mount out of 1/8" steel that will hang the filter down in front of the tank and keep it vertical, which will make changes less messy. As far as the flow goes, it will be right before the fluid goes back into the transmission.

Coolers are another issue. The factory cooler is on the driver's side in front of the AC condenser, and it's plumbed after the radiator cooler. I can see why they want it replaced - it's a plate and fin type and it would be very difficult to flush out any metal particles that might be in there. I'll mount the new Hayden cooler (also a plate & fin) in the same location. The steel lines come close, then have one of those wretched Ford quick disconnects to attach them to a short length of rubber hose. I'll cut them just below the quick disconnects and connect with standard hose clamps.

The extra cooler is going on the other side of the radiator, and I think I'm going to plumb it before the radiator cooler. My thinking is to dump a bunch of heat out of the fluid before it hits the radiator, thus reducing load on the engine cooling system.

Then, in cold weather, the radiator will help warm it up to a good operating temp.

That's the plan for today, anyway. I'll post some pics when I get it done.

 

Good news on the RMS then---having the trans out is a huge benefit.

Ford's requirements to have the full 3 year warranty don't seem like bad ideas at all. So far over three different used E250's I've not had any trans issues---if I did and my trans rebuilding guy wasn't available I'd definitely go the Ford reman'd unit.

When you settle on the spin-on replaceable filter look on Amazon for the Motorcraft number or its equivalent---I buy the FL820S's (engine oil) by the dozen for just over $3.50 each.

Have also bought Valvoline Hi-Mileage motor oil 5.1 qts for right at $16 each, ordered 12 twice at that price. I have enough now for the remaining life on my '03 E250.

 

I just looked those up, and I see they are the shorties. Compatible with the same filter base, but I prefer to run the larger filter on my vehicles. I can get the Wix 51515 on Amazon by the case for about the same price.

Who makes the Ford filters? Anybody know?

Anyway, I got it done, and found a great place to mount the filter. I posted some pics on another thread. I like the setup, though I may play around with better routing for the lines from the filter.

 

I believe our resident former FoMoCo trans engineer suggests the fluid first hit the radiator then the auxiliary cooler. I'm not one to quibble with Mark as he's personally performed extensive temperature monitoring on more than a few Ford-designed transmissions.

 

That makes sense
putting it before the heat exchanger (rad/cooler combo) just cools it to get heated up again

 

If you prefer a larger oil filter and yours uses the FL-1A with the factory oil cooler then look at the FL299. This is the filter for the 370/429 truck motor and is the same diameter, but about 1-1/2 longer. This filter sticks out past the crossmember and makes it easier to get a filter wrench on the filter. Your oilpan gasket may be the 1 pc, try tightening the oil pan bolts to stop the leaks. The bolts do work loose over time with this gasket.

 

What does he say the routing should be when there are TWO external coolers, plus the radiator?

 

The radiator cooler is there for one of two reasons:

1. To heat the trans fluid up to operating temperature.
2. To cool the trans fluid.

It's one or the other, right? No, it could be both. It heats it when cold, but prevents it from overheating by transferring heat to the engine coolant.

But it's not doing both at the same time. It's doing either #1 or #2 at a particular time, or it's in between where nothing much is happening because the temps are equal.

So why is there a factory cooler AFTER the radiator cooler?

Simply because the radiator cooler doesn't always extract enough heat from the trans fluid. More cooling is needed.

Sooooo, that means that mode #2 is the usual operating mode. You are taking heat from the trans and dumping it into the engine coolant, but there's too much heat for the radiator cooler to handle it all, so an aftercooler is needed.

Therefore, dumping heat out of the trans fluid BEFORE it hits the radiator heater will reduce the amount of heat added to the engine coolant, and reduce the temps coming out of the radiator cooler into the aftercooler.

If you only have ONE external cooler besides the radiator cooler, of course you put it AFTER the radiator cooler.

But it doesn't automatically follow from that, that having TWO other external coolers means they should BOTH go after the radiator cooler.

 

I doubt much (if any) of this occurs, the cooler is in the bottom (cold side) of the radiator. As such it takes a pretty long time until the coolant in this side of the radiator is warm enough to transfer heat to the transmission fluid. By the time this happens the transmission fluid is already up to operating temperature. Even when the engine coolant is at operating temp (190-210) the coolant temps in the bottom tank aren't anywhere near this warm. If it were, the radiator wouldn't be doing it's job and the coolant coming out of the heads into the intake would be far higher than 190-210. But don't take my word for this, try feeling the bottom hose next time you've got the engine at normal operating temps. You'll find it's not too hot to touch.

 

I can't speak for him but a WAG would have him saying: "TWO external coolers aren't necessary......" I'd add they MIGHT be a restriction the transmission would be better without.

Again I cannot and will not speak for Mr Mark Kovolsky!

 

Well, says they ARE necessary to get the 3 year warranty.

Odd that they don't say anything about where to put it, though. I really expected some kind of instruction packet or sheet on those extra warranty requirements, but there was none.

As for restriction, I don't think there's any additional. The pre-cooler I chose is a tube-type with 3/8" tubing, where the stock lines are 5/16". Adding a couple of feet of 3/8" tubing isn't going to do anything.

If you want to find some restriction, look at the external filter they require!

That's partly why I went with the bigger filter - less restriction.

 

Agreed. I listed to cover the theoretical possibilities. Heat can flow either way in any heat exchanger; it's just a question of which side is hotter.

It might happen that way if the vehicle were warming up while parked, perhaps.