01 chevy blazer transmission problem

[jstutz]

Guys, today i just went outside to do a quick over on the blazer before the trip and uncovered a very scary sight. My transmission fluid is the color and consistency of brand new motor oil. Honey brown and even smells like oil. What the heck is this. The truck is an 01 4wd two door blazer with 195K miles on it. Maintenance schedule has been this

36k miles transmission fluid, M1 synthetic
80k miles transmission fluid, Advance auto brand DEX3
115k miles transmission fluid, M1 Synthetic
165k miles transmission fluid, Valvoline dex6

Now the truck has 195k on it and i figured its a nice day and i would change it, but i think i now have a major problem. The truck has felt very sluggish lately. Not slipping but just not firm shifts. Shifts are very soft and i feel like sometimes when i hit the gas, that all the power is not getting to the ground.
As far as i know, there is no way for foreign fluid to get into a transmission right? Should i just do a couple of flushes or what. Thanks very much for the advice. I should add that during all previous transmission fluid changes I have changed the filter also and that the fluid has always looked and smelled like good transmission fluid.

 

[Kuato]

A few of thoughts --

First is that you should go back to one of the other fluids where you got better results, and see if there's an improvement.

Second is that a flush in a higher mileage vehicle can do more harm than good, since junk is bound to get moved around and maybe get where you don't want it. A pan drop and refill twice in the next 50k with M1 might be a good idea.

Third I tried to stay away from, but 195k is a pretty good run for most automatic transmissions [I'm not familiar with your vehicle though] and it might be getting towards rebuild time; however I'd try other options first and see what you get.

 

[Kuato]

Oh - forgot one thing and edit is disabled.

I had a similar issue with slow shifting and somewhat sluggish; installing a shift kit in the transmission can help with that if the rest of the transmission is ok.

 

[jstutz]

thanks for the response. Well i have a update. I pulled the pan off and the fluid, although looks clearish on the dipstick, is actually black once in the pan. Im talking jet black. If you dip you hand in it and pull it back up, it looks like used motor oil. I guess i was mislead a little by the looks on the dip stick. I think i might do a good flush on it and if it happens again or if it starts acting up or something, i might just send it down the road.

 

[OVERKILL]

Originally Posted By: jstutz
thanks for the response. Well i have a update. I pulled the pan off and the fluid, although looks clearish on the dipstick, is actually black once in the pan. Im talking jet black. If you dip you hand in it and pull it back up, it looks like used motor oil. I guess i was mislead a little by the looks on the dip stick. I think i might do a good flush on it and if it happens again or if it starts acting up or something, i might just send it down the road.



And to echo what others have said, use one of the other fluids you've had better luck with this time.

 

[GMBoy]

With the fluid being jet black, that can't be good. Sounds like the clutches are all worn. That clutch material could be whats all in the fluid causing the dark color. It may be rebuild time

 

[jstutz]

Well i pulled the transmission cooler line and drained as much fluid as i could and refilled with dex 3. The system is still not cleaned out but it shifts noticeably better. i plan to pull the pan off this weekend and do a fluid and filter change with ST dex 3. i will continue this until the fluid look pretty and pink. After this, i will probably do a few 5k or 10k changes. I drove the blazer today and it really runs great. Transmission feels fine. I just cant imagine how its worn out. Is it possible that the dex 6 just didnt agree with the transmission. I know its backward compatible and probably not the reason but it was the last fluid i used. Or better stated, if the transmission is worn, then maybe the dex6 is not the best fluid to use.

 

[Kuato]

Originally Posted By: jstutz
Well i pulled the transmission cooler line and drained as much fluid as i could and refilled with dex 3. The system is still not cleaned out but it shifts noticeably better. i plan to pull the pan off this weekend and do a fluid and filter change with ST dex 3. i will continue this until the fluid look pretty and pink. After this, i will probably do a few 5k or 10k changes. I drove the blazer today and it really runs great. Transmission feels fine. I just cant imagine how its worn out. Is it possible that the dex 6 just didnt agree with the transmission. I know its backward compatible and probably not the reason but it was the last fluid i used. Or better stated, if the transmission is worn, then maybe the dex6 is not the best fluid to use.


Yeah the new stuff (for all makes) is supposed to be backwards compatible...if it was 100% they wouldn't make the old stuff anymore.

Our auto transmissions were designed around fresh fluid, glad yours is working well after the change. I have a friend whose transmission was going out, he changed the fluid, it got better, and he repeated every 20k or so until it was working normally. He got another 150k out of the vehicle.

 

[Ramblin Fever]

Have a GM transmission too; it does NOT like the Dex 6.....I switched back to Dex 3 over 40k miles ago with no long-term issues.

The Dex 6, IMHO, is too slippery for the older transmissions.

 

[The_Jeff]

Originally Posted By: fredjacksonsan

Yeah the new stuff (for all makes) is supposed to be backwards compatible...if it was 100% they wouldn't make the old stuff anymore.


And the old stuff is cheaper. I wish either ford or GM licensed the old spec, this "DexMer-3" (carefully avoiding trademarks) is a "take-our-word-for-it" deal for the oil companies.

 

[jstutz]

Well i pulled the pan down today again and changed the fluid and filter. Ill keep doing this until it looks nice and red. Hopefully it is not too fouled up. It drives great, shifts good, no slippage or anything. Ill just baby it along and see what happens.

 

[FL_Rob]

'Baby it' is the operative phrase here,with 196k on mine(g20 van),I really take it easy on the starts and I let up on the gas to let it upshift under little load.Fresh fluid twice a year.

 

[jstutz]

Just wanted to update. After a couple more changes with ST dex 3, the blazer is still running and shifting fine. For whatever reason the dex 6 did not seem to be compatible with this particular transmission.

 

[kasedian]

Hmmmm. I have an ol 1999 Chevy Blazer LT. It's the 4wd 4-door model. I fairly sure it has the same transmission as yours. Ive never had a problem with the transmission. It has about 180,000 miles on it now. I've dropped the pan and changed the filter every 50K. This last time, I refilled it with Castrol Dex VI. Now I know it's not full-strength Dex VI in the system, but it seems to be running fine.

 

[jstutz]

I know of a few people that have had good luck with dex 6 in the same transmissions. You will also hear of people that did not. My truck had about the same amount of miles on it as your did and i changed it with Valvoline Dex 6 and it did not take it long to start looking and smelling burnt and shifting very soft and sluggish like it was slipping or something. Now that i flushed all that nasty stuff out, it is staying nice and red with no burnt smell. Maybe i just have a weak transmission or something. Like i said above, with the M1 it still looked new and red when i was ready to change it. For me im just going to keep doing 30 to 50 K mile changes with cheap dex 3 and not worry about it.