Trans slip when pulling toy hauler

How many miles have you done? Is the trans correctly filled with oil? Why do you think its slipping, when it changes up is there some delay in forward pull from the engine that gives similar symptoms to clutch slip? Its not that old and a well maintained trans that hasn't done much towing should do 150k without problems. Towing heavy trailers kills auto trans.

you have to find out why it's overheat ,trans.pipe bent,cooler restrictions,
the pcm know trans.overheat and goes to default mode
have code retrieve

I had a similar problem thinking my tranny was slipping. Turned out it was the spark plugs miss firing, had 100,000 mi. Changed the plugs & wires problem went away.

I would start
by changing both trans filters and fluid, makesure you put dex VI in trans then if still having problems take to someone with a Tech 2 scanner and have them reset the trans adapts and try that, what it does is resets trans to factory (new) mode and then as you drive the truck it will adjust to your driving habits and shift points, but loosing pressure makes me think one of your filters is partially plugged...there is a spin on cartridge and the internal one in pan, change em both..good luck

No transaxles make 100,000 miles

What your saying, including the rebuild
is common

Asian transaxles & all Van type vehicles,
are something you don't want to own

I used to own a trans shop,so I will leave
you with that

Can't fix slipping,drive a couple of days,
& your pulling the trans out again

There is no overflow on the Allison Trans, something happened when the trans got over heated, it is a good idea now to also get a trans flush as once you heat it up that bad it starts to break down the fluid.

These are common symptoms and usually mean the worse.IT is possible you have a bad pressure control solenoid but this is rare.I would start with pulling codes if any are present.Good Luck.

The tag is about the only way to tell. But if it is push button you should have a 246.

You are your own best judge on that, i got a 95 silverado with 160,000 mi. and would not think twice about driving and pulling anything across the country, but one thing i would recamend (if it dosent have one already) is an external trans. cooler.

change the trans oil our it could be low