TH350 Transmission Slip, No Gear, Stutter

[bnations]

I just recently installed a new aftermarket radiator on my '79 camaro with 350 motor and TH350 AutoMatic Transmission and now the thing is either slipping out of gears, stuttering, or shifting erratically at high RPMs. I just changed the fluid and filter on the trans a month ago, and now when I check the fluid level it is very high and grey in color. I have hooked up the aluminum lines coming off of the trans right back into their proper locations on the radiator, is it possible Im getting coolant in my transmission?

How would I go about checking this?

[MagicRat]

Originally Posted by bnations

is it possible Im getting coolant in my transmission?

Is the ATF a foggy reddish/grey/green color, with the consistency of a milkshake?

Yes, it's possible the trans cooler in the new rad is leaking. If so, the ATF may leak into the rad, until the cooling system pressurizes, at which time, the coolant will leak into the trans cooler lines and contaminate all the fluid.

Is there any trans fluid in the coolant?

For a test, disconnect both transmission cooler lines. Then place a coolant pressure tester on the rad and pump it up. Normally, the tester should show that the cooling system is holding 15 lbs pressure for a considerable period of time, at least 10 minutes or so.

Look for a pressure loss and/or coolant dripping out of the trans cooler ports on the radiator.

You can rent or borrow a pressure tester at many auto parts stores.

[j cAT]

Originally Posted by bnations

I just recently installed a new aftermarket radiator on my '79 camaro with 350 motor and TH350 AutoMatic Transmission and now the thing is either slipping out of gears, stuttering, or shifting erratically at high RPMs. I just changed the fluid and filter on the trans a month ago, and now when I check the fluid level it is very high and grey in color. I have hooked up the aluminum lines coming off of the trans right back into their proper locations on the radiator, is it possible Im getting coolant in my transmission?

How would I go about checking this?

If you did get coolant in the transmission ,,,you will need a new transmission...this type of damage destroys everything...including the torque converter...all lines need be carefully cleaned ....

where did you get , and what brand was this radiator