psycledad

Hope someone can help with this as I'm not sure what to fix. Here is the story (sorry for the length) hope I can explain.

I have a 4L60E in a 93 Chevrolet, using threads from this and other forums I rebuilt it using new clutches/steel plates you know all the stuff that comes in a kit. Put in in the truck and shifted great but had a leak around the front seal.

Took the tranny back out and discovered a hairline crack in the pump housing. Found a used pump on flea-bay that had the same casting and advertised as a 93-94 pump which is supposed to be the only years that fit.

Put it back together and back in the truck and here is the problem it wont shift out of 1st.till about 40 mph then goes into what I think is 3rd gear. checked fluid level and all electrical plugs. the only thing changed from original test drive and now is the pump. Could a bad pump cause it not to shift correctly?


Thanks for any help you can offer.

mrvedit

My only current suggestion would be to get a trans pressure gauge ($45 on flea-bay) to verify that the pump is producing enough pressure. Sounds like it might not have much pressure until the engine reaches a fairly high rpm.

Did the replacement pump come with the pressure regulator valve and boost valve? You might want to check that this area is assembled correctly; this can be done after only dropping the pan. I show the parts in the correct order in the upper part of this picture:



Did you rebuild the pump? If yes, did you remember the o-ring and metal ring underneath the rotor? Did you remember the filter on the side of the pump, as in this picture?



Disclaimer: I have limited experience with "broken" transmissions and none with such early ones.