Thread: 700r4 trans. wont shift

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I recently bought a 83 blazer with 2.8 and 700r4 trans. seals were leaking so pulled trans and replaced front and real seal along with new filter . put trans back in and now trans will not shift . Have adjusted t.v. cable properly. and have even checked gov. still wont shift. only paid 125.00 for it but it runs excellent and looks decent too. before I pulled it it shifted fine after wont shift .have set t.v. cable correctly!!!! hummmmm

No shifting at all?
Fluid level?
Is gear selector adjusted correctly, not hanging between gears, etc?
TV cable is hooked to trans, moves freely, and is adjusted right? ( i know you said that like 3 times...but never overlook the obvious!)

Rear seal is idiot simple, so on the front - did you get the converter seated all the way in? (three 'clicks' or what have you as it goes onto the splined input shaft(s))?
If all this seems to be 100%, then on to the filter... been a while since i've had a trans pan off, but i have had things fall out...and many trans have notes regarding 'gotchas' on filter replacement - you gotta be 110% sure you did that right! No falling BB's, to double gasketing or non-gasketing, etc.

I would suspect the filter is at fault, or the install of it...there is a pressure tap on the trans to check pressure - i can get the specs if you need it and have a guage - if the filter is blocking a passage, no or low pressure will make shifting, umm, odd to say the least.

You say it won't shift. Does that mean it won't go out of 1st? Have you pushed the engine to the end of the RPM band to see if it eventually changes? If it does'nt, then it's in the valve body. Remove and dismantle it whilst ensuring that all the valves and springs are stored in correct relationship - u can use a piece of corragated iron roof sheeting to rest them in perfect positioning. Or get a piece of cardboard, place a ruler against its end and bend the cardboard to make triangular corrugations. Works well. You don't have anything to loose. That's what i'd be doing as I found several stuck valves in my time that caused havoc. Sounds like a stuck one - two shift valve mate! No rocket science here. Most probably it's been caused be the entry of some foreign matter in the vavle body. I'd say it's entered the hydraulic system during replacement of the pump seal as that is an area where clean filtered fluid enters. From there on the dirt would go straight to the valve body. Just before I go, did you ensure that the throttle pressure cable has spring tension on it? It may be not returning. It needs to pull out and retract without any binding at all.... Good luck. Rob