4l60e question

[MudDigger]

ok i got a 96k1500 with the 4l60e and after about a 50 mile trip it will start slamming 1st-2nd and torque lockout stops working any ideas?

[Jthomas]

The tps sensor can cause the slamming or 'shuttering', especially noticeable or at its worst up hill. (Not sure if this is what you are experiencing)

Also, you can't have the TC locked up and shift through gears. Bad stuff happens.

It may not be the transmission itself, there's a lot of electronics that controll the transmission. Tps being the cheapest, I would start there. I'd get it scanned and see if it's in range. Or get someone with an O scope to scan it while doing a throttle sweep. See if you have a smooth waveform.
Could also be the fluid pressure switch, or the pressure controll solenoid.

If that's not the issue, then I'd go get the solenoids checked. If the TC lockup solenoid was getting stuck on, so the TC wasn't unlocking, shifting would be slamming for sure.

Btw, your going to want to check these while the transmission starts acting up.

And if it's not electronics, then you could have physical damage inside the trans. Wich would require an overhaul


There's a couple other trans guys on here that might chime in



First things first, get it scanned. Because it's just shots in the dark till we get a code.

Good luck!

[MudDigger]

Thanks bud ill have it scanned

[camok10]

If you have code p1870 it's generally caused by the pwm valve in the valve body for the torque converter. They are know to wear the bore they sit in and cause issues. Sonax and transgo both have fixes for them. I've had the transgo hd-2 kit in a couple trucks because of this issue.  All of them had the same issue, once the truck gets warm and cruising steady speeds for a while the check engine light will come on and the next take off it snaps your neck on the 1-2 shift. This is because p1870 is a trans slippage code. The computer commands full line pressure to prevent it from slipping.

[MudDigger]

thats exactly what is happening how much did it run ya to get it fixed?

[camok10]

The kit summit sells, I don't rember the price. I just got them rebuilt and upgraded when it happened. I had a beast sun shell, 5 pinion planetary, if the drum allowed 9 friction and steels put in the 3-4 clutch pack instead of 7, 2-4 corvette style servos and the transgo kit. I've never had a problem with a dd 4l60e set up like that.

Here's the transgo kit

http://m.summitracing.com/parts/trg-4l60e-hd2