My transmission was flushed and filter changed 6-7 years ago but that was only like 17k miles. I do qualify as severe duty but miles arent high enough. Over this amountof time does the fluid breakdown?

 

ah yeah i flush and change my trans filter every 15 20 thousand miles and my blaze is an 91 with 143,000 thats just my preference though

 

Changing a trans filter that often is a waste of money IMO. The only thing to clog a transmission filter is parts of the transmission.

Next time you have the pan off, install a drain plug and then just drain the pan and refill every 20-30k miles if you really abuse your transmission (towing, lots of shifting, etc).

One thing that will dramatically improve the life of the trans fluid (and transmission) is adding a cooler.

 

+1 to swartlkk...
I've replaced filters on two different trannies and neither of them were clogged. I think the metallic dust in the fluid passes right through the filter because the pan is always filled with it. Seems to only pick up big chunks. Fluid changes are a great idea though (no need for a true flushing.)
If you have access to a welder, drill a hole in your pan big enough for a bolt to fit through. Screw on a nut so its on the inside and tack it down. Take oout the bolt and finish welding (so it doesn't seize up for some reason). Thats how I made my own drain plug.

you can check your own fluid by looking and smelling it. wipe the dipstick on a white paper towel and see if its red. and smell it. if it's brown or burnt smelling then would not hurt to replace it at all.

 

I have done the trans drain mod a few different ways. Before I bought my welder, I used the B&M drain plug kit that worked like a charm, but did leave quite a bit of fluid in the pan (still you replace around 5-6 quarts which is almost half the dry capacity of the transmission).

Recently, I helped a friend weld in a nut which was lower profile than the B&M kit and we just bought a replacement oil pan plug to use in the trans. Had to cut it down to keep it from interfering with the filter, but that's no problem.

For my Rainier, I'm going to be pressing in a recessed area in the bottom of the pan about 1/4" deep, then I'll weld in a nut and again use a replacement oil pan drain plug to seal it up.

Trouble free fluid changes for the life of the vehicle with a lower profile than the B&M kit!

 

Heat from extreme duty does cause the fluid to break down. heat also causes the gaskets, seals to harden, which leads to leaks and that leads to slippage which leads to more heat, and the cycle continues until total failure.

As swart eluded to, the tranny is a closed system and the only thing to plug up a tranny filter is the tranny parts, typically clutch pack matelial, yep that metalic stuff in the bottom of the pan and yep ythe filter is doing its job if the metaliac stuff is in the bottom of the pan, its not in the tranny eating up seal/gaskets/o-rings.

The best thing for tranny longevity is a tranny cooler, drive so the tranny isn't constantly hunting for a gear, and drain the pan every 15,000 (severe duty), 30,000 regular duty. Top off with tranny fluid of your choice, Dextron III is recommended and the tranny is one place where the synthetics makes a huge difference, if you can afford it. Regular tranny fluid costs about $4 a quart and your systems holds 11-12 quarts roughly $50. Synthetic is about double that.

 

flush only if there are floaters, sorry hadda do it.. Been a long bad week..

 

Ok since I am past 15k on the fluid andI meet many severe duty criteria, ifimgoing to drop the pan to drain out the fluid should I just change the filter since I already have it open?

 

Yes, not because the filter needs it, but becuase the filter kit cost like $15 and comes with the gasket you need. Since your replacing the filer, make sure you do the fiolter gasket too. Dont leave the old one in there and stuff a new one on top of it.

While you ahve the pan off, install a drain plug.

Make sure the gasket mating surfaces ont eh tranny and pan are cloean with brake cleaner. Do not use a rag. the hair/fibers in the rag is enough to stop a valve. on;y takes a piece of a grit the size of a grain of salt to stick a valve. too fic=x it you ahve to drop the valve body. Dont do this on a windy day. Do not use gasket sealer either.