What "pump" leaks in a 700R4

[Skunksmash]

I had my trans fixed for about $800 a few years ago when I got the truck. It was leaking and I'm fairly ignorant on the guts of an automatic trans. The guy wanted to do a full rebuild for $1500, but I said that I just couldn't afford that. So he said that he could just fix the leak and do a few other minor things including the rear main seal, for about $800 after everything.

I didn't know enough about the auto trans and still don't even now, to understand what "pump" was causing the trans to leak. Anyone know? Something I've always been curious about. Cause I really don't like not knowing what a mechanic is talking about when I have to have something worked on that I can't just do myself.

[terryj]

The only "pump" you have in an automatic is the converter pump, it is the business end of the torque converter. If your transmission is leaking the most common places for this is, front seal (this is where the torque converter enters the transmission body), the rear seal or the transmission lower pan.
The rear seal and the pan gasket can be replaced with the transmission still installed, however, if it is the front seal then you'll have to remove the transmission to replace the seal. If you have fluid leaking from the front of the transmission then it is most likely the front seal.

[Skunksmash]

Thanks. Seems it was worth the $800 I paid for the job. Sounds like a lot more work than I would have wanted to do. Or could have done.

[INSIDIOUS '86]

If the seal does not have a groove ; on some transmissions the drain hole behind the seal gets covered up by the converter seal and does not vent properly. $800 for a FULL rebuild is an ok deal. $1500 and that guy better be giving you a built trans
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[gchemist]

700R4s leak at the front input shaft bushing. The pump/case seal rarely fails, but does. The brass bushing is easily replaced.