OK, I've got a question for the resident transmission experts here. I pulled the 4R75W out of my 2005 4X4 with 105k miles on it because it had a pretty bad leak from the bell housing. Well it looks like the leak was the pump seal blowing out. It's not the seal around the output shaft, it's leaking from the bolt holes in the pump body itself. The truck was shifting and running fine, just leaking badly.

So I want to rebuild the pump and put the transmission back in the truck but I don't know where is the best place to get parts. I know there are transmission parts places all over the internet but if anyone can recommend a good place that would be great. And if anyone knows where a write up or information about rebuilding the pump is that would be great as well. I've got a rebuild manual for the older Ford transmissions but nothing for the 4R70 / 75 tranny's.

So what do I need to know before rebuilding the pump on my 4R75W? What is the best place to get the parts that I need? Are there any special tools required? Thanks guys!

 

Wow! That sounds like a big project. Good luck man, sorry I can't help with finding parts.

 

Thanks for the info Crash. I was hoping someone would chime in on this thread. I've got a new question now.

I've got the pump out and now I'm trying to figure out exactly whats wrong with the pump. As you can see in the picture below it was leaking from the two lower bolts.



Well I've taken some pictures of the area of the pump that was leaking as you can see below:











You'll have to forgive me because this is all new to me. But from what I can tell there is nothing wrong with the pump. Heck, it's just a gear pump there's not a lot that can go wrong. And the best that I can tell the only thing that was leaking was the seal behind the pump. It had transmission fluid on both sides of the seal like it was leaking past it. But, the seal did not look damaged either.

I think that I may only need a new seal but I'm worried about simply replacing a couple of seals and going through all the work of putting the transmission back in the truck and the truck still leaking. Should I replace the whole pump while I'm there? Or would you guys just replace the seals and stick the transmission back in the truck?

Also, where is the best place to get the parts that I need to fix this leak? Do I just need to get them from Ford? Thanks for the help guys. Any help is appreciated.

 

Thanks for the reply Crash. I did clean up the housing before I took those pictures. It was leaking very badly, much more than seepage. The housing was completely dry except for the area under the location of the leak so I am assuming that is my only problem area.

This is the area of the seal at those two bolt holes that were leaking and it looks fine but it had a bunch of transmission fluid on both the front and back side of the seal at the location of the leak but the rest of the seal was dry indicating that transmission fluid had in fact been leaking past this seal at those two bolt locations. It wasn't a small path where the fluid was leaking, it looks like it was the entire area.



My only real hangup is that the seal looks to be in just fine condition. No rips, tears, etc. It looks almost like the bolts backed off a little and didn't hold the proper pressure so the seal started leaking. I now wish that I didn't use air tools to remove those two bolts so that I could have taken notice of the torqe needed to remove those two bolts.

I think I'm just going to go with the re-seal and hope it works. I can't see anything else wrong with the pump as it looks to be very good condition. I could probably replace the pump bushing while I'm there though. Thanks for the help and the tips. The tip to use the bolts with cut off heads as an alignment for the seal is a good one.

You mentioned using grease to ensure the seals don't get cut. What type of grease would you use for this? Thanks again!

 

Most would recommend a tranny assembly lube that dissolves in to the ATF. However, for such limited use as in this case, I think you're fine using a multipurpose grease. Just make sure the pump gear is installed correctly. The the steps on the flats should face the front of the transmission as they'll engage the corresponding flats on the torque converter. Also make sure that the bleed hole in the intermediate piston lines up with the half-moon in the pump support. Having this bleed hold badly misaligned can cause slow 1-2 shift engagement.

Personally, I would replace all the seals while you have things out of the truck.

EOAZ-7D020-A Plastic Pump Seals (x2)
3L3Z-7D019-AA Metal Pump Seals (x2)
F2VY-7A248-A Front Oil Seal
2L3Z-7A248-AA Square Cut Seal that goes around the circumference of pump
F2VY-7A136-A Pump gasket

 

You know you just responded to a thread where the last post was almost 3 years ago?

 

Ha! Well, I'm sick as dog and am home with little else to do. I guess this page doesn't get much traffic.