I have a 2002 GMC z-71 with 97,000 miles I need to service the transmission fluid and filter change. My question is what is your opinion on "flushing" the trans to help remove contaminants. I have heard alot of mixed reviews on this over the years so what say you ? Also what do you do about the fluid inside the torque converter ?

just get a filter kit, drop the pan, replace filter, refill trans.  you will be fine.  if that 4l60 has made it this far with no troubles, then you should be good to go

I don't recommend "flushes" Especially when done by quick lube places where the workers can ALMOST read.

Do a basic drain and filter. I wouldn't worry about the quart or two in the converter.

Most of these "flush" services were invented to sell machines and sell services. I've never found them to have any benefit to the customer.


YMMV.

My old 97 Mountaineer has a drain plug on the torque converter, so I always drain both the tranny and the torque converter.  I disconnect one of the lines to the transmission cooler in front of the radiator and stick the end of the hose into a gallon jug; crank vehicle and much of fluid from the pan is pumped into the jug, making removing the pan much easier.  

Many of the "flushers" don't change the filter.  I wouldn't recommend a flush.

there are cases when the flush machine do work, like torque converter shutter. fliuds do break down, and cause issues. one thing that the trans flush does, is exchange once for once of trans fliud, dropping the pan will not do that. there is alot of discussion on "wallet flushes" and both sides have merit. our trans guys will NOT do a filter and gasket service on certain units, the the new fliud will break down old fliud and cause issues, back in the mid 90's Ford engineering had our trans techs do complete flushes on certain units. but we get ALOT of screwed up services from the "jiffy lube" places and our on Quicklane, the BG bladder system will not exchange the proper amount of fliud in certain vehicles, and being they don't have dipsticks, that causes trouble.

on your chevy trans flush, maybe a chevy tech will drop by if we have one, and give you the real dope on the trans service you need. i know this will cause wailing and nashing of teeth, but maybe calling the dealership for your brand would be helpful, sometimes you can get a good guy that will lead you in the right direction

thanks for the info vote... I am still undecided

I work at Cadillac and service the Escalade transmissions and we use a flush machine that replaces 12 quarts of fluid in the tranny while the vehicle is running.  Most of the fluid is in the torque converter so a drain and fill replaces very little.

If you have never had your transmission serviced before now, you are probably screwed either way.

A Chevy 700R4 taught me a long time ago not to follow the manufacturers specs. I have mine serviced every 30K miles.

Accountant

Last filter change was at 50,000