Converter slipping? Fifth or sixth gear clutch?

[yellow is good]

When I'm towing heavy, cruising down the highway(interstate), pulling one of the many hills in the Green Mountain State, It feels like something is starting to slip.

RPMs move no more than 200 I would guess, I don't let it continue, back off immediately. Truck has never limped the transmission. Happens around 90% load according to the edge. It'll do it in 5th and 6th gear and I think it may have in 4th as well.

The fact that it's doing it in multiple gears lends me to the torque converter, since I know they were never strong in these trucks. Getting ready to start pulling some more hay this year expecting to see it again.

Been a long time since I posted here, hopefully my signatures correct. If it's not the truck it's a '06 Crew cab short bed, has 200,000 mi on it, I installed a transgo JR I think at 50,000, maybe before.

Rebuild time, or should I keep being nice to? Not a new issue...

 

[Mike L.]

Scan it and get a code. Code should be a P0741.

 

[yellow is good]

Hi Mike, I have enjoyed reading your posts over the years on different forums

Scan it and get a code. Code should be a P0741.

When I scan it with my Edge it says p0502 vehicle speed sensor low input. That happens when I use low range has since I got the truck.

Using EFI live AutoCal no DTC's, which I think is because the code read by the Edge is stored, no check engine light.

 

[Evan@InglewoodTrans]

Very often there is no code present with converter slippage. It’s very simple to diagnose though. Just watch converter slip when lock up is commanded with a scanner and see if it’s indeed the culprit. You’ll want it to be just about zero if it’s doing what it should be. There may be a very minor + or - depending on what you’re ready slip with which is normal.

 

[Mike L.]

P0502 is a speed sensor code. Hook up a scanner and watch all 3 speed sensors.