2000 Trailblazer hard shifting and no torque converter lockup

2000 Chevy Trailblazer with 65000 miles. After driving about 1 1/2 hours the transmission will not go into "lockup". Several days ago I did get a "Service Engine Soon" light and the code was a P1870. The light went out several days later. The transmission shifts normal til driven for an extended period then the 1 - 2 shifts are "hard" and also 2 - 3 is somewhat hard and it will not go into torque converter lockup at this point. Transmission was serviced by the dealer at about 50000 miles.

Help !!

Thanks

MikeyM

Hi Mikey,

I have the same problem on my 97 blazer, and I found that the p1870 code is "Transmission comp. slipping". Whatever that means.

kphilbin, the component that slips is usually the torque converter. In the valve body the TCC apply piston wears on the body itself allowing quite a bit of the apply pressure to leak by. There are a couple companies making kits to repair this without replacing the vavle body(GM's fix). I think the companies are transgo and Superior transmission, not real sure

Thanks for the help Jeremy! I'll check out those companies for the kit.

I have another question:

I found the transgo transmission kit on ebay for a very reasonable price. Some people are offereing new seperator plates too. If I am installing the trans kit, should I go ahead and replace the plate too?