I recently acquired a 96 S-10 Blazer with all wheel drive and about 71K miles on the odo.
The vehicle had a BAD trailing throttle gear whine which I attributed to a bad pinion bearing in one of the diffs.
I continued under this impression until, during one of my routine tranny pan drain and fills (been doing it every 1000 miles trying to clean up the fluid), I added a bottle of red lubeguard and within about twenty five miles, the whine was markedly reduced. After about 750 miles, it returned to its original level. Other symptoms indicating transmission problems were an intermittent 1/3 to 1/4 second delay before the tranny would "hook" up, and a complete inability to keep the tranny fluid clean. I could drain the pan, and within twenty five miles, the new ATF would look like motor oil.
The fix, as many would guess, was as simple as changing the filter. The prior owner never bothered to change the filter, probably never bothered to drain the pan, and it was full of sludge and almost completely plugged. Only aboout 15-20% of the surface area of the filter was available to pass ATF to the pump. Fortunately, no metal bits in the pan, but plenty of sludgy gunk.
New filter cured all the gear whine, hesitation, and the fluid is now looking good. I now have 75K miles on the vehicle.
For those that are interested, the vehicle gets Mystik SX-8 10/30 PAO blend, Harvest King (Mystik) ATF in the tranny and transfer case, and Mystik JT-7 80/90 in the diffs.
The vehicle had a BAD trailing throttle gear whine which I attributed to a bad pinion bearing in one of the diffs.
I continued under this impression until, during one of my routine tranny pan drain and fills (been doing it every 1000 miles trying to clean up the fluid), I added a bottle of red lubeguard and within about twenty five miles, the whine was markedly reduced. After about 750 miles, it returned to its original level. Other symptoms indicating transmission problems were an intermittent 1/3 to 1/4 second delay before the tranny would "hook" up, and a complete inability to keep the tranny fluid clean. I could drain the pan, and within twenty five miles, the new ATF would look like motor oil.
The fix, as many would guess, was as simple as changing the filter. The prior owner never bothered to change the filter, probably never bothered to drain the pan, and it was full of sludge and almost completely plugged. Only aboout 15-20% of the surface area of the filter was available to pass ATF to the pump. Fortunately, no metal bits in the pan, but plenty of sludgy gunk.
New filter cured all the gear whine, hesitation, and the fluid is now looking good. I now have 75K miles on the vehicle.
For those that are interested, the vehicle gets Mystik SX-8 10/30 PAO blend, Harvest King (Mystik) ATF in the tranny and transfer case, and Mystik JT-7 80/90 in the diffs.
