I Need to know if anyone out there knows if I can use a front pump from an 87-up on an 86 700r. I know they went to the axillary valve body, and I think there were more vains in the pump. I have an 86 700r4 in my firebird that I rebuilt but the only pump I currently have is from I think an 87 because it has the axillary valve body. Thanks to all in advance.

 

You need to plug the oil feed hole for the aux vb, but otherwise, yes you can use it. That said, you still need to diss-assemble it and check/replace everything as needed. The vanes and hardened rings are cheap, so is the up-graded slide spring. Just put a large worm-clamp("hose clamp" - or multiples tied together if need be) around it to properly center it when you tighten the halves back together.

 

Yes this is a rebuilt pump with Trans go Parts. So just to make sure you can use this pump as long as the Axillary valve body hole is plugged? Thanks

 

the reverse input drum is different, the input shaft is different. You should replace all as an assembly, and plug the aux oil feed hole. That is the correct way to do it, but requires a different torque converter to complete the job. there is a different hole size requiring a plug with a small hole in it that can be screwed into the feed for the reverse input drum also giving the correct rev/input apply.

 

Thank you very much. So if I replaced the 86 front pump with the 90 front pump and only plugged the axillary hole this would account for a lot of problems which I am having, correct? Such as the car will work fairly good in reverse but slips and wont shift in drive and seems to lock up if I put the selector in 1st..

 

Anyone? I'm still fighting with this any ideas what would cause this? Could it just be the pump?

 

Did your's still have a 27 spline input shaft? I hadn't thought about that and I haven't looked at one in so long I can't remember if any of the apply seals/orifices changed. - sorry if I miss-lead you.

I don't think the pump change could effect more than the rev apply/release charicteristics, and even then it would almost have to be a 92 or 93 pump to cause noticable issues.

I have had several that used the first rendition of the 10-vane pump(87-91) with the early reve drum w/o isue, but I have not used a 27 spline input shaft.

 

No sorry you didn't mislead me. I rebuilt my transmission and ended up having to use a different pump(opps amateur mistake on the old one), and when i got it together I'm having the problems I described earlier. If you know anything else that I could have done wrong please feel free to help. Now I have torn it all the way apart again and I am rebuilding it according to a book. Thanks for hanging in though I appreciate all the help.

 

Not sure what book you have, but the ATSG manuals are worth their weight in gold.

 

That's the one I've got I couldn't remember the name off the top of my head. Glad to know others like it. So far I'm really liking it, it sure beats trying to figure it out on your own.