I installed a new Nissens radiator in my 2000 Volvo S80 2.9 with 168K miles on it and now three days later the transmission is pulsing and the check engine light has come on. I did not replace the small amount of transmission fluid that drained out when I disconnected the lines from the radiator because the fluid level on the dipstick was over the full mark before I started. There was some bubbling showing up on the dipstick following the new radiator installation and I assumed this was from the air gap left from draining the radiator lines. The last transmission fluid change was done about 50K miles ago.










Could the cause be a defective radiator where the engine coolant is leaking into the transmission line? Or perhaps I should have replaced the small amount of transmission fluid that was in the radiator tube?
My options are 1) flush and replace transmission fluid and replace filter thru a combination of dropping the pan and via the transmission lines 2) take the car to a local Penzoil garage for a machine flush and fluid replace via a machine or 3) have the car towed to a transmission repair specialty shop.




This car otherwise runs so great and is in such good shape that I'd like to keep it.




Your advice appreciated.

 

If there is water in the transmission then I think you will find evidence of that. Should not be hard to diagnose. It usually looks like chocolate milk (red and green makes brown). Water and transmission fluid mixed will be really opague because it's an emulsion. Like milk, basically.

 

The transmission dipstick level with the engine cold is a good inch over the full mark, so I think its safe to assume that the radiator is defective and leaking engine coolant into the transmission lines. The car is not driveable so I think at this point my best bet is to pull the radiator out and have it tested at a radiator repair shop.

 

Good luck! Stinks that would happen with a new radiator.

 

I extracted a small sample of the transmission fluid from the engine and had a transmission repair shop test it for glycol for $75. They initially wanted to tow my car to their shop but I didn't want to surrender control that easily. After finding out that there was no trace of engine coolant in the transmission, I was relatively confident that I could drive the car a short distance without damaging anything, so I went to AutoZone where a free computer scan revealed that one of the ignition coil packs was bad. I installed a new pack and now everything seems fine. This wasn't the smoothest operation I've ever done, but my confidence to affordably keep my 16 year old Volvo by working on it myself is is almost back to normal. As always, I learned a lot.