P1870

[bluebear15]

i have a check engine code P1870 which says trans component slipping. drives perfectly fine except sometimes i will get a hard 1-2 shift. was told it might be a back TC switch so i replaced that and it was back to normal for a couple days but then it returned. my tahoe has 209k mi on it and i was told by the previous owner when i bought it back in oct that the tranny was rebuilt by the previous owner to him about 5yrs ago so it roughly has about 60k mi on the rebuild. the previous previous owner was a tech at a saturn dealership so i assume he knew what he was doing.

any ideas on what could be throwin the code for me?

 

[///RAGMC]

When was the last time you seviced it?

 

[Hodges87]

I'm having the same problem with my moms 97 Chevy C1500 5.7L. Its a problem with the TCC apply valve bleeding pressure in a worn valve body. In most cases this is an easy fix without a rebuild or new valve body. I'm going to buy a new TCC apply valve and write a "how to" on how to fix this problem. Here is a link to the TCC Apply Valve http://www.transmissionpartsusa.com/4L60E_TCC_Apply_Valve_for_PWM_models_p/400-0077805ek.htm

In your case I would install the Transgo HD2 and a new separator plate and you should be good to go, that's what I plan to do in my 97 Z71

 

[bluebear15]

When was the last time you seviced it?

i bought it back in oct of this yr and did a trans service early nov the fluid was just starting to look/smell bad when i did it

I'm having the same problem with my moms 97 Chevy C1500 5.7L. Its a problem with the TCC apply valve bleeding pressure in a worn valve body. In most cases this is an easy fix without a rebuild or new valve body. I'm going to buy a new TCC apply valve and write a "how to" on how to fix this problem. Here is a link to the TCC Apply Valve http://www.transmissionpartsusa.com/4L60E_TCC_Apply_Valve_for_PWM_models_p/400-0077805ek.htm

In your case I would install the Transgo HD2 and a new separator plate and you should be good to go, that's what I plan to do in my 97 Z71

that'd be sweet if u could do a write up. i dont plan on fixing this until spring when its warmer out lol also whats the transgo hd2?

 

[Hodges87]

The Transgo HD2 is probably the best shift kit on the market for the 4L60E, but you can just replace the valve and that should fix the problem. I plan on doing this job after the first of the year.

 

[bluebear15]

ahh ok. what are the benefits to a shift kit?

 

[Mike]

I had the same problem, local tranny shop installed a specific fluid flow improver to fix this common issue.

 

[bluebear15]

I had the same problem, local tranny shop installed a specific fluid flow improver to fix this common issue.

know of anywhere to buy this? i dont want to take it to a shop

 

[Mike]

They have to completely disassemble the tranny to do it. Unlikely you're ready for that.

 

[bluebear15]

ya ik i'm already looking at dropping the valve body. i'm cool w/ doin the work. my dad was a GM tech so he knows whats all involved