86 transmission question
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Advanced
Joined: Dec 2004
Posts: 82
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From: Kalamazoo MI
86 transmission question
I recently had the fluid changed on my trans. with 69,000 on it. I had noticed before the change, that the car would shift early in the RPM range under normal acceleration. When I had the service performed I asked the (very reputable) mechanic if he could check it out. He made an adjustment and it seems to shift at a resonable RPM when the car is warm. However, I have noticed that the car has to wind up to approximatly 3000 RPM before it will shift, for the first 5 miles when the car is cold, and shifts hard. After the car warms up seems to shift OK. Should this be cause for concern? Any input would be appreciated.
Burning Brakes
Joined: Nov 2000
Posts: 855
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If the TV (Throttle Valve) cable was set properly before you took it in I'd be concerned, because if you mess with it to adjust your shift points your really messing with the line pressures of the trans and that could lead you back to your mechanic for a rebuild. Do a search on this forum for setting the TV it is easy and requires no tools.
Intermediate
Joined: Nov 2005
Posts: 39
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700 shift stuff
86 models still have hydraulic shift only 700R4 transmissions. The TV cable setting is certainly important, but remember, if it ever shifts properly, you can assume the TV is set right. Good shift cold but bad shift hot, or vice/versa means a different problem. If the TV was wrong it would not shift right regardless of temperature.
I think you have a sticking valve (probably the TV valve). The only component besides the pump that is upstream of the valve body that sends unfiltered oil to the TV valve & valve body is the torque convertor. After it passes through the convertor, pump, valve body & rest of trans it falls to the bottom of the pan and is then filtered before going back to the pump. You can see that if a conv is making metal, it goes straight through the pump and valve body and has the potential to stick valves. If there was a lot of metal in the pan then I would certainly prepare for a trans teardown/rebuild. But goofy shifts do happen as a result of a little trash in the system. If there was not a lot of metal in the bottom of the pan during the service, then aggressively give the valve body a good work out by lots of manual up****s and downshifts. That is what tranny guys do right after a rebuild with stubborn shift trannys. Try it, you wont hurt it.
I think you have a sticking valve (probably the TV valve). The only component besides the pump that is upstream of the valve body that sends unfiltered oil to the TV valve & valve body is the torque convertor. After it passes through the convertor, pump, valve body & rest of trans it falls to the bottom of the pan and is then filtered before going back to the pump. You can see that if a conv is making metal, it goes straight through the pump and valve body and has the potential to stick valves. If there was a lot of metal in the pan then I would certainly prepare for a trans teardown/rebuild. But goofy shifts do happen as a result of a little trash in the system. If there was not a lot of metal in the bottom of the pan during the service, then aggressively give the valve body a good work out by lots of manual up****s and downshifts. That is what tranny guys do right after a rebuild with stubborn shift trannys. Try it, you wont hurt it.
