Preferred Transmission Fluid Change Method?

Taking the '96 Aurora into the dealership next week to replace the fuel rail. Thought I'd kill two birds with one stone and have the transmission fluid replaced at the same time (currently 95K miles).

I checked with the service department of two local Old's dealers and was told that they drop the pan and replace the filter (screen) in the pan. This method only replaces approx 60% of the fluid in the system.

I checked with the local Goodyear Dealership and was told that they use the flush in place method where they open a line and introduce new fluid into the system while pumping out the old fluid. This method results in a 100% fluid change. They do not remove the pan or change any filters. He said that the current thinking is that it is better not to open a transmission and disturb any seals or gaskets unless you are experiencing operating performance issues.

I mentioned that I had read on the internet that the transmission has 3 filters, and he said that may be so - he wasn't sure. He also said that all filters are merely screens - not the filter assemblies from days of yore. One of the 3 filters in the transmission is reachable only when doing a major disassembly. So, it didn't make a lot of sense to open anything up.

Should I not worry about any metal shavings that have accumulated in the bottom of the pan? I guess the screen should / would prevent them from being introduced back into the system...

Anyhone have any experience or opinion on which method would be better in my case? (Not that it matters, but the Goodyears service is $30 less than the dealer's service).

if you have a 96 it should say you fluid is still at 100%, like mine still does 8 years along...according to the owners manual unless you tow a trailer,use it in a hot city, 90 degrees average or in a region where you are constantly climbing hills,taxi and police car use.it isnt necessary to change it.that being said if your going to do it properly do the gasket and filters first, replace the missing fluid,then do the 100% flush....my motor mechanic teacher used to say about transmissions that didnt receive regular interval flushes ,dont start fixing it when its working good.check the condition of the fluid ideally it should be cherry red when new,purple is dirty but still acceptable,if it stinks or it looks more like motor oil yes change it and make sure they add a conditioner to the 100% refill

Right you are. I just checked the owners manual and it said to change the fluid every 50,000 miles - IF driven under the described harsh conditions. Otherwise, the fluid would be good for the life of the vehicle. As you say - my DIC shows the fluid life @ 100%.

I had the 100,000 mile figure in mind from reading the scheduled manitenance list @ My GM Link www.mygmlink.com It merely said to change the fluid and filter every 100,000 miles. No if, and or buts...

Out of curosity - I stopped at the local Chevy dealership on the way home and casually asked about transmission fluid changes. They said 1) they drop the pan - they don't cycle the fluid for a complete flush and 2) Why do you want to change it - are you having problems? The service manager went on to say that he was from the old school - if you aren't having any problems - then leave well enough alone and don't touch it.

I know some folks that have their fluid changed every 20K miles (non-aurora) - they swear it extends the life of the transmission and avoids any problems. I thought I'd emulate them and try to follow the recommended 100K change even thought the computer shows fulid life @ 100%!

Based upon the facts as presented - I guess I'll save a few dollars for the time being - and defer any maintenance.

Thanks for the feedback!