TH350 3rd gear slipping?
Hi all! I'm John and I'm new to the forum. My hotrodding days are few and far between these days due to spending most of my time with an '83 CJ7, but I still do what I can to eek out whatever performance it'll give me. I have swapped a GM SB into it with Holley EFI and a TH350. The TH350 is where I'm having the problem and I've noticed that you all seem to have some very knowledgeable people on this forum, and I'm losing my mind trying to figure this one out, so I thought I'd ask.
I just recently had this tranny rebuilt. After I put it in, things seemed to be working fine. When the tranny is cold, it shifts perfectly - I've adjusted the modulator to set the shift firmness where I like it. However, once the tranny warms up, 1 to 2 always shifts fine, then 2 to 3 shifts fine but will only seem to stay in 3 for a short while. After that it seems to slip. If I pour the RPMs to it, it will still pull a little, but I can also shift it down to 2 both manually and through the kickdown and it works normally. Reverse works fine. I do notice that 1 is tighter than normal, but, other than that, it works fine. Someone told me this could be the governor, but I'm just not convinced. Do any of you have any thoughts on this?
I realize that my post doesn't fit in here just right, and I apologize for that, but I really do appreciate any help you might be able to offer.