Should I flush transmission or just replace fluid/filter?

[metolious69]

I've a 2000 4WD Tahoe with a little over 100,000 miles. I haven't done any transmission work since I bought it at 70,000 miles. And I'm unsure of what transmission maintenance the previous owner did.

I'm having no transmission trouble but thought it may be time to flush or just drain and replace the fluid/filter. I've heard mixed reviews on doing both. I'm looking for recommendations. I don't want to flush the system and then start having tran problems that I didn't have before. Not sure if the old saying fits "if it ain't broke, don't fix it".

Any help/advice appreciated.

[wafrederick]

Do not flush,replace the fluid and filter.My father knows a guy that has his own transmission shop that does valve body cleanings because someone had their transmission flushed.The lines are above the filter and where does the dirt go during a flush?,in the valve body and the valves stick.I had to replace one transmission because it was flushed and acted right up after the flush.

[gkindub]

metolious69, check the color of your tranny fluid against new. If it's not bright red in color you need to change fluid and filter asap. Consider using synthetic if you plan to keep the vehicle awhile. While you're at it you might want check your owners manual for 100k service intervals for Fr & Rr Diff's and transfer case.
Regards, gb