Changing tranny fluid in older vehicle

[parkertown]

New poster here with a question.

I've "inherited" a 1994 Chevy K1500 4x4 from my dad. Even though the vehicle is 12 years old, it only has 42000 miles on it. In the last 5 years it has only been driven about 1100 miles per year, and I don't see that changing. In reviewing the service records, I discovered the transmission fluid has never been changed.
I've heard several horror stories about how changing the ATF in an older vehicle can cause more problems than it may prevent, but I was wondering if that would hold true in a vehicle with this low a mileage.
Would you guys suggest dropping the pan and changing filter and fluid, doing a transmission flush, or just leaving it alone? For additional info, the truck runs like new and the transmission shifts fine. The fluid also looks and smells fine. What would the BITOG folks do with this truck? Many thanks in advance.

 

[unDummy]

Drop and clean the pan, change the filter, and go from there. 42k miles is not quite old so don't worry about. And, with the pan off, you might want to install a drainplug to do regular future partial drain/refills.

 

[parkertown]

Thanks! Dropping the pan and changing fluid and filter was whaat I wanted to do, but was hesitant with the truck being 12 years old and still on the original factory fill ATF.

 

[Ken2]

I'd do an Auto-Rx 1000 mile cleaning, then a complete flush including dropping the pan.

The bad rep about flushing transmission oil usually comes from folks that had a transmission problem in the first place. The transmission was dying, they flushed the fluid, the transmission died anyway, and the flush got the blame. The blame should have gone to themselves for not changing the fluid periodically before the transmission failed.


Ken

 

[Islandvic]

parkertown, I have a "new to me" '95 K1500 GMC Z-71 with 168k miles and orig trans filter and fluid.

I just drop'd the pan, cleaned it, installed a drain plug, and new filter, and refilled with cheap WalMart Super Tech DexronIII.

The next week I drained and refilled with more cheap SuperTech, and added 1 and 1/2 bottles of LubeGuard AT Protectant.

I used the AAMCO version, but the original version is in the red bottle.

All is well and no trans sliping, shudder, or delayed shifts. No leaks either!

He are some pics.

http://www.supermotors.org/users/islandvic


I reccomend a pan drop, filter change, drain plug install, and refill. Then drain and refill once a year for good PM.

Good luck!

 

[bxd20]

I've heard "horror" stories of these aftermarket drain plugs backing out... somehow I find that hard to believe, if done right.

Can someone pelase explain what brand of AM drain plug works well, and what the process is to install one?

Thanks
Brian D

 

[Islandvic]

bxd20, Mine was from MotorMite at NAPA.

I used Permatex High Heat Threadlocker to secure the nut to the bolt. It wont be coming off anytime soon.

I just drilled a 1/2" hole in the pan and installed.

Check out the pics on the link above.