julian734

My friend and I both have 2001 5.3 Tahoes. We have always heard the stories of peoples transmissions going bad after getting a complete change of the fluidover 100k.We were told by some mechanics that thats not true and if it goes outit wasNOT because of the servicing. Well we both are around 100k and that when the book says to get it serviced , so my friend did it first andguess what??? TRANNY'S ACTING UP!!Please help..should I just never change my trans fluid??...Thanks - Joe

ZX1100F1

What exactly is the transmission doing now that isn't right?
Generally speaking; if a transmission is in good condition the act of simply changing the fluid and replacing the filter will not harm it, in fact this procedure is recommended (at 50,000 miles if towing, 100,000 if not towing) so that you achieve the maximum life from the transmission.
There are cases when a transmission will fail after servicing, this is usually caused by either an improperly completed job (usually over-filling) or a transmission that is damaged already, if a transmission is damaged and on it’s way out a servicing can expedite a failure or bring to light a small flaw.. It is also not advisable to service an old transmission that has been abused and neglected for many years.

julian734

He said its not changing gears properly. for instance it will shift too late at high rpms.

ZX1100F1

Is it setting a SES light on the dash?
Make sure that you check the tranny fluid level.
Do this after the truck has been driven for at least 20 minutes (preferably at highway speeds) then park on a level surface and leave running move the shift lever into each gear possition for several seconds and then return it to PARK and set the Park Brake, with the engine running romove the transmission dipstick and wipe it clean then reinstert it and remove it and inspect the level of the fluid, the safe operating range is within the "HOT" crosshatch band on the dipstick.

paradisepatiosAZ

I heard the same thing that ZX is saying about an "abused" transmission (I prefer to call it "well used") from a service director ina local dealership. I had an '01 Z71 Silverado and used the heck out of it. Pulled a 6000 lb trailer all over the Texas hill country, got it stuck in the mud and used 4x4 mode to pull it out (often) and drove it daily for 3 years. At around 100K I asked this dealership if I should change the fluid & he asked me if it was acting up. It did shift into gear a bit hard / with a clunk, but drove fine. He then asked how much longer I was going to keep it. I wasn't towing anything anymore and planned to sell it w/in a year. He said let it be, if not I would likely have to replace it before I sold it. Well I put another 31K on it before I traded it in and it never acted any worse than it did at 80K. It's a gamble, but I'd save up some cash & drive it 'till it breaks. You'll probably make some decent interest on the money you put away to replcae it!

wreckless123

If you think about it, it would be possable to have an issue magnafiy itsself after a fluid change. If all the friction material was almost off the clutches and the old fluid is changed which is dirty and contains all the clutch material floating around in it, I could see a slight slip turn into a major slip. Either way the trans was about ready for a rebuild..