2009 silverado 4.8l 2wd
Basic work truck, standard cab, 8foot box.
340,xxx km's on it.
No lights or pending codes
Maintenance up to date

​​​​It tows a all aluminum 7x12 enclosed trailer (max 3000lbs with load) as needed which is every couple of weeks. Always use tow/haul mode when trailering.

Bought the truck from my father in law as he bought a newer work truck. The trans was rebuilt almost a year ago and I've had the truck about 5 months.

​​​​​When I first got it regular driving it shifted like normal. If WOT it would shift extremely hard/violent to the point where I would lift just before it shifted.


As of yesterday it seemed to hunt between drive and overdrive while using cruise control at 90kph on flat ground.
Also will no longer downshift if I go WOT to pass a vehicle at 90kph, manually shifting doesn't change anything either.

​​​​​​If i got WOT from a stop it will shift through all gears but no longer shift violently.

Fluid it up and still bright red.

The trans shop that rebuilt it is 4+ hours ​​​​​​away.
​​​​
​​Does this sound like a servo problem?
Will I do damage if I drive it?
Did I provide enough information to make an informed guess as to the cause of my problem?

Thank you for reading my novel.

 

You can use the attached instructions too check the servo pin travel.

 

Well the truck drives like normal again for the last couple of days.

​​​​​​It down shifts as it should.
The shifts are not violent and are just a tad firmer than factory shifts at WOT.

Should I do anything or let it be???

Thanks

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