1st Gear Poster
Join Date: May 2005
Location: Middlefield, CT
For what it's worth, 4R70W rebiuld
Working on my bro-in-laws 99 GT mustang, everything was going well. He and I decided to tackle this ourselves because it was slipping a little (80K), so maybe we could get away with a rebuild kit and some misc parts and a good inspection. We bought a stock reman T/C ($219) and a master Alto rebuild kit ($300), a 5.4L truck pressure solinoid, stock OD & Rev bands. When it came time to do the seals for the tailshaft, I decided to go with factory cast iron seals, the front one was real bad, worn down and the latch tab was "gone". Looking in the back bore of the case it was apparent that just replacing the seals was nowhere good enough. The bore was trashed where the seal hits it (.015"). So, having a machine shop, I hung it off the table of the Bridgeport and bored it .125" oversized and turned up a press-in sleeve. Deep hole drilled the ports back in. This is not a normal wear surface, the seal is supposed to remain atleast somewhat stationary. The shaft looks fine, maybe a little (.002") wider, but smooth. It was good to find out what the problem was though. We'll be doing a flush and new cooler also.
One reason I'm posting this is because alot of people trash rebuilders (which I'm not) and mechanics when the cost of a quoted repair has "surprizes" once the job is started. Some sh** is unavoidable. Most, if not all, repair shops have no way to fix this type of problem, or even know about it in advance. I don't know how much a replacement case is, but I'm sure it would add significantly to the cost, and completion time.
Thoughts and comments welcome.