Transmission Trouble, DTC 39, 68, 83

[rj]

Would appreciate input on a transmission problem:

1995 K2500 6.5TD Suburban with 4L80E transmission, 113,000 miles.

TCC quit working 2 days after some hard towing with a 6000# travel trailer. Otherwise, transmission operates fine and no problems shifting.

In OD the transmission sets the following codes:
DTC 68 (Transmission component slipping)& DTC 83 TCC PWM Solenoid circuit fault).

In 3rd gear the transmission sets DTC 39 (TCC Stuck off).

Codes will clear, but are set again after reaching TCC lockup speed.

I have been to the dealer and a transmission shop. Dealer said transmission is shot and need a new one. Got 2nd opinion from transmission shop, which said the problem is in the electronics.

Thanks in advance for any input.

[More Power]

The book says:

DTC-83 Could be due to a faulty ignition switch. Restart, then turn switch back slightly.

DTC-39 & 68 Clear the codes, then drive in 3rd till hot, and give several hard accelerations. If code 39 appears, converter slip is the problem. If no codes in 3rd, but 68 appears when 4th is selected, the problem is 4th clutch pack.

When was the last time the fluid and filter were changed?

MP

[ 11-12-2003, 12:33 PM: Message edited by: More Power ]

[rj]

Fluid and filter were changed 11 months ago (approximately 6,000 miles). I haven't pulled the pan, but the transmission shop said that the fluid looked great.

More Power, you mentioned "the book says..." Which book do you have and how thorough is the troubleshooting?