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TH700 harsh engage in "D"

  • Thread starter Thread starter m nordin
  • Start date Start date
M

m nordin

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Hi,

I bought a -84 earlier this year. I do have one problem with it: When I put the tranny in "D" it whacks in the gear very hard. Reverse feels OK - just a smooth normal feeeling.

One thing I noticed is that this is only when the tranny is warm it shows this. when cold it almost feels normal even though the idle is higher then.

Idle speed seems OK, No slip in any gear. Yeah, I know TV cable is important to check but the car is 1000 km away from me now...

Anyone recognize these symptoms?

Thanks.

Morgan Nordin
 
Hey Morgan. I recognize the problem. My 84 does the same thing. My 700R4 was rebuilt just over 20k miles ago. I replaced the U-joints and the rear hub bearings and the jarring affects aren't so prominent but still slams into drive pretty hard. Sorry to say I'm not sure why it does this or how to adjust it so I'm curious as to if there is a fix for it as well. Good luck.
 
I'm no trans expert, but it do sound like maybe the TV is out of adjustment and giving you too much pressure at idle...though I don't know if that should have the same effect in reverse or not.

Bill
 
Thanks for the input! So I am not alone with this problem and the TV cable came up again. Just a thought - if the TV cable is too tight at idle and gives a "whip lash" engaging, then I wonder how high pressure the tranny gets at WOT?

I have looked in the workshop manual to see if there are any accumulators in action together with the forward clutch but on my poor scanned copy I cannot really figure it out. A brocken spring or a stuck piston in a accumulator can give thes symptoms.

BTW are the early TH700 so much weaker than the later ones with 30 (?) spline input shaft. Really neccesary to upgrade the pump in a car with almost stock horsepower?

More help needed...

Morgan Nordin
 
You do need to readjust the TV cable and as an added treat...switch to Valvoline synthetic tranny fluid. Made my 85 tranny shift as smooth as a caddy.
 

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