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Slow to respond when first started

882 views 4 replies 3 participants last post by  1981monte 
#1 ·
I have a TH350 and when I first start my car after a long winter sleep it takes a little while for the trans to work. It did this last year, and again yesterday when I started it. What happens is R nothing, D nothing, L1,L2 it is slow to engage. I do not try to drive, I hold the brake rpm@ 1100, I run the shift selector P,R,N,D,L2,L1 and back up again until it feel's like it engages all gears, Fluid is full and clean I checked thinking that was the problem.

Is it normal for this trans. sitting all winter or is there something I should do before I store it this year. Or before I start it next year? After it I get it to work it is fine for the summer :thumbup:
 
#2 ·
Your trans has converter drain back issues. The weight of the fluid in hte converter will drain back into the trans pan over time. A vehicle that is stord for long periods may exhibit these symptoms. The best thing to do is let it run for a few minutes, in any range, and double check the fluid level after this short run-in period. As the car is running , the trans will refill the converter. There is not much you can do to prevent this. Just recognize it as the condition it is and enjoy your car.
 
#3 ·
It sounds to me like you may very well have hardened seals on the apply pistons in your turbo 350. As far as convertor drain back issues, the trans puts out enormous pressures and when the vehicle is started it will fill the convertor very quickly.

When a transmission is rebuilt, the convertor is basically empty, and the delay to engage is not an issue.

If the transmission has not been rebuilt or if it is an old transmission, then the seals will harden allowing the fluid the be pushed past the seals instead of pushing the lip seal out againt the sealing surface.
 
#4 ·
Is it normal for this trans. sitting all winter or is there something I should do before I store it this year. Or before I start it next year? After it I get it to work it is fine for the summer
This indicates the reason for my response. Hard lip seals react the same regardless of time spent unused. The cooler pressure of a T350 will not exceed 80psi. Since this is the same circuit that fills the converter and its pressure is dictated by RPM, there will be a lag in filling the converter after long static periods. Most cooler circuits operate at 50-60 PSI at an idle mainline pressure of 60-75 PSI. When the converter is full of air, the trans will not turn.
 
#5 ·
I do have an external cooler, and it is mounted near the top of the rad. which puts it higher than the trans. After I got it to engage in all gears and took it for a road test to make sure the trans. was OK I changed the converter from stock to a 2300 to 2800 stall converter that I bought from Roadrunner converters in Arizona.

As long as this slow start each spring is not an indication of a problem I am happy. If it was a sign of a problem I would rebuild it or replace now.
 
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