ford 1990 f-250 7.3l lariat 2wdr auto, big big leak between at the base of the bell housing !!! got stuck on the road and tow at home. A few Q

how good are those transmission, any upgrade to make them better?
at 200 000 miles is it time for replacement or rebuilt? It was working find up to now.
I don't use the truck very hard, but will do a big trip soon with camper slide on.
How hard it is to drop those unit, and if the big leak is just a seal, can i replace it my self? where can i get the part?
how many hours in a shop I am looking for? any body with similar experience, Any info will be a big help. Thanks

 

200 000 miles is a lot for that type and year of transmission if you can verify that its a factory build. Its beat the odds and although some make it longer, most do not.

Most likely a blown front main seal and this is a very common problem that often comes with overheating. Were you using it a little harder when it happened? Maybe trying to back a trailer up an incline? Was it doing anything abnormal?

There is a better aftermarket seal that is more heat resistant then the factory silicone seal (has blue on the actual sealing surface instead of being completely grey). It may in fact still seal back up after it cools but it won't hold for long even if it does. If you have ever replaced a pinion seal on a differential, then you can replace the seal on the transmission. They are pressed in the same way. Just be careful not to scratch the aluminum bore.

I don't have a lift or proper transmission jack, and it takes me a good 6 hours to drop my E4OD, however I drop it with the transfer case on. About as long to put it back in. Thankfully, I haven't done that in a long time.

Yes, it can be upgraded. How far you want to upgrade really depends on how much you want to spend because it may cost as much as an engine rebuild if you want completely bullet proof. I rebuilt mine myself and regretted a few mistakes but would do it again if I had to.

For buying a replacement, your options are wide, but from my understanding, BTS makes one of the strongest ones out there. Ford dealers also offer reasonable prices and warranty that most smaller shops cannot compete with. The ford factory rebuilt transmissions have lots of internal upgrades that make them very reliable in a stock application. For heavy towing or turbocharging however, they are not quite enough.

 

yeah. i vote front pump seal too.
hey not bad! iv never had a tranny seal last 200k before.front or rear.
replace 'em both while your at it.the rear is easy to do anytime sure,but with 200k it cant last much longer i wouldn't think lol.changing it now sure beats another break down beside the road and lost of trans fluid.
if your not using the truck real hard,just putting in a shift kit and cooler is a good place to start.the shift kit reduces clutch slippage which= wear,and heat.and the cooler helps keep things cool.
changing the fluid and filter every 50k is a good idea as well if working her regularly but not overdoing it.

ps.yeah with making good camping runs,and just a slide on.i wouldn't worry about rebuilding it if its working good.there are LOADS of upgrades for serious haulers who hook on to 15k+ plus all the time.for us who may haul a couple tons once in awhile,id just do the upgrades noted above.(use heavy duty mode to firm up the shifts.dont go any higher,or it will pound you lol)

 

It is HIGHLY UNLIKELY that a stock E4OD installed in 1991 would make it 200,000 miles without at least one rebuild, no matter if it had a cooler on it or not. There were design flaws back then that could only be fixed with hard part upgrades.

Yep, pump to converter seal got old and hard.

An auxiliary trans cooler does wonders for helping a trans last longer.

The forward piston's inner seal should have also hardened and worn a deep groove in it by 100,000 miles or soon after, not to mention the center support and the forward clutch metallic sealing rings would have serious leakage issues and deep grooves as well.

The newer center support bearing design was an upgrade needed from day one.

 

thanks for the info , because of those e40d problem, is it possible to put other serie of transmission ! is it possible!

 

I'm glad you asked!

You might want to reply with the rear end ratio and tire size you have on the truck now so I can answer any question you have in the reply.

The C6 would be a perfect swap for the ID Diesel E4OD.
It bolts right in to the engine and the cross member can easily be made to fit, and it still uses the old style speedometer gear and cable.

The E4OD was designed from the C6 using most of the C6 parts and design.
There are a lot of parts that will swap into the C6 from the E4OD so some of the E4OD upgrade parts will fit into the C6.

And there are three things that effect the over all Final Drive Ratio.
1: The transmission's high gear ratio.
2: The rear end ratio.
3: The tire diameter.
As you go down the list, the items get easier, and cheaper to change.

There are a few things that need to be changed out to get the C6 to work/fit.
1: Pulling the electrical F.I.P.L and put in the variable vacuum control "switch?" and the related hoses.
2: Changing the drive shaft length to fit the shorter C6 or the longer C6/Gear Vendor combo.
3: Wire in the neutral safety switch plug with the wires that are already there to fit the C6.
4: If you want to, the gear indicator under the speedometer, but it's cosmetic and not needed.

You will loose the high (overdrive) gear the E4OD has as the C6 is a three speed and has no 4th overdriven gear, but depending on the rear end ratio in your truck, you could swap the rear end gear for a taller set, or if you have taller tires that can compensate as well.

There is also the Gear Vendor Overdrive that will make the C6 a 6 speed with a 2 speed reverse!

The E4OD has an overdrive ratio of .72
The gear Vendor has a ratio of .78:1

I have the 3.55 rear end gears and with the stock overdrive it gives me an overall final drive ratio of 2.56.
If I swap in a C6 and get the 3.08:1 rear gears I will be going from a 2.56 to a 3.08 so a little worse fuel mileage but a much more reliable transmission.
These are the available ratios times the OD ratio to give the final drive ratio
3.08 X .72 = 2.21
3.55 X .72 = 2.56
3.73 X .72 = 2.68
4.10 X .72 = 2.95
4.56 X .72 = 3.28

So if you now have a 4.56 rear end you can swap in a C6 and a set of 3.55 gears and not lose much, but if you put in the 3.08 gears you will be ahead of the E4OD.

The Gear Vendor will get you.
3.08 X .78 = 2.40
3.55 X .78 = 2.76
3.73 X .78 = 2.91
4.10 X .78 = 3.20
4.56 X .78 = 3.55

Taller tires can have a huge effect on the ratio as well.
A truck with 4.56 gears stock with 29 inch tall tires acts, or feels like a 4.00 rear end when you swap in 33 inch tires, and is just like having 3.00 rear end with 44 inch tires.

That is why those with taller tires need bigger gears, so you can adjust the FDR with taller tires.

 

Alot of useful info but two things I have to disagree with. Not as important for some is the indicator for gear selection. Many states require this for inspection and even if it works but doesn't line up correctly, they will fail you.

Most importantly is the reversing part you spoke of. Absolutely NOT true for GearVendors unit. These units, also known as Laycock OD's, absolutely can not be used in reverse. The unit will be "fighting" itself and totally wipe out the sliding cone clutch or worse. You maybe confused with the US Gear unit that's offered.
Also with the unit in theory you have a six speed, but only if your generating enough pump pressure which is driven off the input shaft of the unit. It's recommended 40+mph to insure the pump is capable of generating the 400psi required to hold the sliding clutch engaged on the planetary drum. So in reality you have 1st gear, 2nd gear, 2nd overdrive, 3rd, and 3rd overdrive. In most cases I find myself at 50mph hitting the switch and going into OD bringing the rpm down to about 1800 from 2400.

I can personally say with the c-6 I built up and the recent addition of the Gearvendors/ Laycock unit I rebuilt, I'm enjoying the truck all over again. I can now do 65mph at about 2400rpm where before i'd be over 3000rpm. And I still have my 4.56 r&p for the heavy load hard starts. Between the IDI and C-6 I appreciate the simplicity and copious amount of parts available almost anywhere. o.k. I'm done.

 

You can get it to line up, but the O around the D would imply overdrive, and that would bug me.
I thought I read somewhere that you could use the GV in reverse, but it might have been the other unit you mentioned.

I'll look into it.

Either way, I prefer the C6 over the E4OD any day.

 

Let's see, there are the....
1: Gear Vendor®
2: Dual Range®
3: Saturn overdrive®
4: RubiCrawler®

Those are all that I can find right now, but there was one that I remember that would start in od if you left it in od and came to a stop, or put it into reverse.

Drive with your foot down, flip the switch and that when you lift your foot for a split second, it would shift.

OH! would you happen to have any pictures of that GV OD you rebuilt while it was torn apart?

I would love to see it on the inside.

 

I have nothing personal against the C6, but after swapping one out with a built up E4OD, I'd never go back. The problem with a C6 and gear vendors, is there is a practical limit to how low you can get the RPMs because the lower they are, the more slip the torque converter lets through.

There is no way to put a locking torque converter in a C6, so no matter how low your final gearing is in theory, it won't match an E4OD.

 

Search the one I mentioned earlier, US Gear. They claim you can use it in reverse.
The only pics I took were of the clutch and the case. Posted are pics of mine during the rebuild and the last pic will be an exploded view of a J type which is similar to the P type. The main thing rebuilding these is cleanliness and test and adjust your pressures to spec 21psi residual 400psi activated. Insuffecient pressure will cause clutch slippage or no engagement.

 

If you want to rebuild your E4OD check out these parts from Oregon Performance Transmission.
http://www.oregonperformancetransmis...gory_Code=E4OD
http://www.oregonperformancetransmis...gory_Code=E4OD
http://www.oregonperformancetransmis...gory_Code=E4OD
also check your torque converter for signs of overheating. I replaced mine with this one, supplied by the transmission shop.
http://www.transtar1.com/technicalHT...2&ppp=35&ppn=2
I pulled the transmission myself, took it to the shop and they gave it a thorough check up and installed the parts for $250.00. The torque converter was an additional $475.00? if my memory serves me correctly.

 

I just did a few searches on the listed overdrives.

Looks like the Dual Range is a modified US Gear unit. Dual Range

Saturn Overdrive looks like it was bought out by Advance Adapters and is out of production. Part may or may not be available. Overdrive
And I did not see where they would be of any use on an F series since I saw no applications for the transfer case or transmissions we have.

Ranger Gear Splitter is another overdrive, but looks like only the four speed transmission works with it, and has to be moved back. Ranger Torque Splitter (V-8 Conversions)

Rubicrawler looks like a rock crawler deep reduction unit only. RubiCrawler 2.72:1 crawler box for the Jeep 42RLE transmission | Engine & Transmission Conversion Adapters - Advance Adapters

So for bolt on overdrives, looks like US Gear and Gear Vendors are about it at this time.

Custom overdrive, A Spicer (Brownie box) with a second shifter could give you under and overdrive in the same box, but custom everything and a rather steep learning curve to be able to split gears while driving.

 

As far as the torque converter slipping, they slip very little at steady freeway speeds, and if, just for example, the TQ slips 10%, if you gear the rear end 20% higher it can compensate.

Most people do not realize that tire height and rear end gearing can effect the final drive ratio so much that it can make the fact that someone has an overdrive trans a non-issue, or more than compensate for that minor bit of slippage in the TQ of a C6.

 

I have never had my GV apart, so I have no idea whats inside of it but it has to be in direct in reverse.