I have the original three speed "Turbo HydraMatic" automatic transmission in this rig, and it was rebuilt within the past two years. Since that time, I have noticed quite a bit of transmission fluid leakage, which I need to address. In the meantime, I continue to add transmission fluid. The question being - what type of fluid should I purchase that is closest to what is specified in the service manual.
Service Manual states: GL-4 GM Type A Armour Institute Qual. AQ-ATF SAE-90 (summer) or SAE-80 (winter)
NOTE: based upon reading the manual, I purchased and recently added Redline MT-90. Prior to that my records show that I added ATF+4. Which means I have both in the transmission oil pan. Should I drain all fluid from the transmission, and replace with the same? If so, what should I purchase?
Service Manual states: GL-4 GM Type A Armour Institute Qual. AQ-ATF SAE-90 (summer) or SAE-80 (winter)
NOTE: based upon reading the manual, I purchased and recently added Redline MT-90. Prior to that my records show that I added ATF+4. Which means I have both in the transmission oil pan. Should I drain all fluid from the transmission, and replace with the same? If so, what should I purchase?
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