Hello. I bought a 04 avalanche 2 months ago with 176k miles for 4k. Recently i changed the transmission Fluid. I noticed the truck to shift a little hard and or delays a little. Not too much, but does it more once the truck it warm up. When its cold transmission seems to shift smoother. Should i be worry? I plan to use the truck 3 to 4 days a week to haul furniture ( no trailer) and plan to buy a new toyota truck in the future. I already spent about 1800 doing some repair to make the truck last longer and i do not want to spend more. Do you recommend doing something to the transmission or do you think it might still last some time? I might only drive 5 to 8k miles per year.
Did it start misbehaving after you changed the fluid or was it shifting harshly even beforehand?
it so:
First of all, check that they used the correct transmission fluid type (I think, that on these automatics it’s ATF Dexron III or VI, check your manual)
and most importantly check that the oil level is correct.
Generally on conversional automatic, especially General Motors products changing the fluid if it wasn’t changed enough beforehand can cause rough shifting.
These transmissions are very sensitive to the fluid condition and for many different reasons changing the fluid once it’s “too dirty” can cause them to slip and cause these kids of issues…
you can try and reset the values stored in the computer by unplugging the battery (at your own risk, I wouldn’t do it)
These transmissions adapt them selfs to the oil condition and general tranny condition so it may be still using the old preset and there’s no guarantee that under the new values it will shift better.
if it was shifting bad not related to the oil change, there’s quite a bit of different common faults on these…
