I think the pump seal blew out

Bowesmobile · May 7, 2015

Driving home today and the trans started kicking out. Made it home and looked underneath the Expy to find the bottom of the trans and transfer case soaked with trans fluid. It was hard to see if the top was soaked as well, but it didnt look like it. Soooo, it looks like I'll be pulling the trans out to check the pump seal.

Bowesmobile · May 8, 2015

I guess the question is this. If I go so far as pullling the trans to replace the pump seal, should I just rebuild it? The cost would be about $500 to rebuild it compared to the cost of the new seal at $10. The trans also has 243k miles on it and I tow with it. So I think yes I should.

Ed_Strong · May 8, 2015

Have you checked the condition of the trans fluid? Does the fluid smell burnt? If there's fluid coming off the top of the tranny vent tube theres a good chance the tranny might have overheated cooking the internals!!!

Bowesmobile · May 11, 2015

I'll check that out. I think the drain plug could have come out of the troque converter. I heard something rattling around in there. We'll see what turns up when I pop off the inspection plate.

Bowesmobile · May 16, 2015

I climbed under the expedition today and the trans is only wet across the bottom. The top is dry and I popped the drain cover under the torque converter. There was trans fluid inside the torque converter housing at the front of the trans.

Bowesmobile · May 27, 2015

Over the long weekend I cleaned out the garage and moved the expy in for a trans rebuild. I drained the converter, then the pan. The fluid is burnt and its time to overhaul at 243k miles. I'd say thats prEtty good. I ordered the rebuild kit from here oregon performance. They were recommended from a rebuild done on the f150 forums. I also ordered the shift kit from Transgo, and Im ordering the HD torque converter from Torque converter 1 . Dont forget the trans assembly lube. I have a rebuild manual and have the rebuild videos from youtube book marked. I'll link one below.

How to rebuild the 4R70W

There are four videos in this series on disassembly, sub assemblies and reassembly. Makes it very easy!

stamp11127 · May 27, 2015

If you want to take detailed pics and do a write up on the rebuild we can make it a sticky in this section.

Ed_Strong · May 27, 2015

stamp11127 said:
If you want to take detailed pics and do a write up on the rebuild we can make it a sticky in this section.

YES... That would be very helpful to others

Bowesmobile · May 28, 2015

I will do my best to document everything. From the videos I've watched and the information on the rebuild I've gathered. Anyone should be able to rebuild their own transmission.

Bowesmobile · Jun 1, 2015

This weekend I drained all the fluids, dropped both the drive shafts, my shift kit, HD torque converter, trans adapter for my jack and Assemblee lube arrived. I'll get more pictures of everything so far. Also there was a rattling that I have found was a shrould that went over the universal joints at the transfer case. It was pretty beat up and Ill have to pull the transfer case to get it out. Im going to see if I can pull everything without pulling the torsion bar crossmember. This weekend I'm not going to get a lot done. My son is graduating and were having his grad party!

Bowesmobile · Jun 2, 2015

Some photos of the tear down. The first one shows the cover that I was talking about in the last post.

Bowesmobile · Jun 2, 2015

Few more of the underside during disassembly.

Bowesmobile · Jun 2, 2015

Goodies came today!

Bowesmobile · Jun 2, 2015

The rest of the parts!

Ed_Strong · Jun 2, 2015

Can wait to see more progress...!

Bowesmobile · Jun 2, 2015

Me too! I just need to get the graduation and party out of the way.

Bowesmobile · Jun 10, 2015

Little update from last night. Pulled the passenger fender well, removed the trans fill tube and unbolted the front pipe from the manifolds. The bolt that holds the trans fill tube in is hard to see but, its a nice little 8mm bolt behind the a/c lines in the picture. I took a cleaner shot about the a/c lines so people got a better feel for where it was. Pictures in the next post.

Bowesmobile · Jun 10, 2015

Here are the pictures. This weekend I am going to get the trans pulled out. Then this thread will really get moving.

Bowesmobile · Jun 11, 2015

I almost forgot one more thing to order is a replacement anti clunk spring! You want to buy the style for the 4R75W. The original 4R70W spring had a habit of wearing through the trans housing then causing a leak. Heres a link to the style you want anti clunk spring

Canadian Expy · Jun 11, 2015

My Expy starting leaking oil from the front seal after towing, It seems to be just small drips now so I might just put a new seal in it.

Too bad you aren't building a 4R100 so I could use the tips.
Good Luck with the build !!

I think the pump seal blew out

Full Access Members

Full Access Members

Full Access Members

Full Access Members

Full Access Members

Full Access Members

Full Access Members

Full Access Members

Full Access Members

Full Access Members

Full Access Members

Attachments

Full Access Members

Attachments

Full Access Members

Attachments

Full Access Members

Attachments

Full Access Members

Full Access Members

Full Access Members

Full Access Members

Attachments

Full Access Members

Full Access Members

Similar threads

Forum statistics

Share this page