I searched. I have read up but I have not seen anyone with a solution. My ‘14 base A6 runs 220 in traffic and when on the highway will drop down to 200 within a few minutes and 175 in 20 mins or so. On cool ambient temps it won’t go above 150. I have an early A6 (#320 made) and it has no trans fan on the rear duct (but does have functional drivers duct with a cooler). . Fluid is 1k miles old.

I read up that Z06 ducts help a little as does a wrapped offroad xpipe. Anyone have any other easy-ish suggestions?

 

For an engine to run temps like that, the t-stat appears to be stuck open. I run pretty close to the same 220 for most of my driving. I had 2 temp spikes up into the hot area and traced that down to a fan controller that wasn't running the fan as it should when I was idling. I replaced the fan with a z06 fan and the problems went away.

Does your car have any kind of a ECM tune or aftermarket t-stat?

Elmer

 

Following.

 

I just traded in my coupe A6.. changed out the fan to the Z06 also as it went to sleep after 30 mile drives without stopping.. It did help but it always stayed at 220 and the oil would fluctuate but mostly stayed 200 or so until you get on it then it would raise... that Z06 fan can move some air and had no issues when it was 115 here last year.. I have a 14 Vert with manual now and will be watching it to see if I need to change it out also..

When it is below 30 degrees the oil temp would stay around 175 or so

 

I have a 2014 Stingray and have been told the gauge on the dash is bogus. After the engine warms up it will show nothing but 220. This is a bogus reading on the gauge found in all 2014's according to post here. You can go to the infotainment system and see the actual temperature digitally which will be in the 195 range. At least mine is.

 

Interesting. Going to have to compare my pocket gauge to the digital readout on mine.

 

I learned this from this forum from people way more knowledgeable than I about the 2014 temp gauge. I believe it only pertains to 2014 and I was very upset with my dash gauge reading 220 constantly. Then found by helpful post I can change the dash readout to see the actual numerical water temp and it runs in exactly the correct range for my thermostat. Somewhere around 195 which is significantly better than 220.

 

Everybody, I read OPs question as asking about the A6 Trans Temps, not engine temp. Maybe not.

Anyway, OP, if you are asking about the A6 trans temps, what you posted are normal in my experience I had with my C6 A6. No need to worry until the temp exceeds 240-250, absolute redline would be 270. Spirited paddle shifting, like in autocross, etc, will get the temp up to 230 pretty quickly but that's about it.

 

Yes! Trans temp not engine! Sorry engine runs normal operating temp. No issues. My trans runs hotter than my damn oil temp sometimes and I am not even at the track - just traffic!

 

This is pretty normal behavior given the transmission cooling setup with just the rear cooler and no fan. The biggest heat generator in an automatic transmission is the unlocked torque converter where the power lost is converted to heat and this is what you see when idling and particularly in stop and go traffic where the most heat is generated with very little cooling. Modern synthetic transmission fluid will take more heat so manufacturers can get away with less cooling. The temperature you are reading is at the sump and it spikes considerably higher at the converter output point.

I haven't read about problems with failures with the A6 due to lack of cooling but if you want to better cool it the best change you can make is to add a cooling fan for the cooler so that it will have some forced air cooling when stopped or at low speed. You would want one with the flexible "shroudlets" which provide good fan airflow across the cooler at low speed but flex open to allow additional air flow when vehicle speed makes the ducted cooling fully functional.

And I hate GM's move to "dummy" temperature gauges. My 2018 GMC 2500HD Sierra Denali has this "feature" for the coolant temperature gauge which will stay at the 12 O'clock position as soon as it warms up and this is one of the reasons I bought one of the Bank's iDash gauges for it so that I can see actual operating conditions in addition to being able to force a regen of its diesel particulate filter when it is getting close to full so that I can make this happen on a sustained highway drive where filter regen is fast and efficient.

 

My 2014 A6 Stingray has a trans cool as standard. please correct me if I am wrong but in 2014 Automatics came standard with trans cool as standard. M7 have no aux cooler. My A6 trans hardly ever gets above 180 on the hottest of days.

 

Yes, the base A6 has a cooler inside drivers side duct but it does not have a fan on it (or at least mine doesn't). Interesting about your temps. mine definitely gets hotter. I am in TX though and traffic can get rough as well as temps over 100 degrees.

 

GM gave up on true linear gauges decades ago. People would freak out in heavy traffic when the gauge would approach overheat conditions. Now gauges "read" three positions, cold, normal, overheat.

 

I think he's talking about the trans temp, not engine temp.

 

Yeah, I picked up on that.

 

Well I am curious about the fan. My build sheet has an RPO code of KNP - Trans Cool. I assumed that meant an aluminum finned or radiator type cooler with a fan that I have seen on You-Tube. Wonder what the RPO code for trans cool w/fan is? I know the duct is not sealed off because I can run water through it and see it come out the rear.