DENALI WITH AUTO TRANSMISSION FLUID IN COOLANT

BFOXY2

MEMBER
GMC

2002 GMC Denali - 57,125 -
Several weeks ago I discovered Automatic Transmission Fluid in my coolant recovery tank, I was told the transmission cooler inside the radiator was leaking and I would need a new radiator, all new hoses and flush transmission and install new filter and fluid. I recently noticed the water inside the coolant tank was reddish in color again, took the Denali back to the garage, questioned the color, thinking I may still have a transmission fluid leak, but, was told that it was GM antifreeze and it was reddish in color. And not leaking again. My question, does GM make an antifreeze that is reddish in color?
: Thanks, Bfoxy2

1 Reply

HEAVYDUTY

MEMBER
60 POSTS

GM coolant (dexcool) is orange/red in color but you are probably going to see residual transmission fluid showing up in the resivoir for a long time because it hangs on to all the metal parts in the engine and doesn't flush out of the rad. When drained. Then because oil floats on water it is on top at the rad cap and gets pushed out of the overflow first when the engine warms up. Every couple days you can try dipping a rag down in the resivoir and the trans fluid will soak into the rag leaving antifreeze behind.