Red08

Cuising along at higway speeds, according to the DIC, the engine coolant temp is usually right around 205 +/- 2-3 degrees. The engine oil pressure is typically somewhere between 35 - 40 psi. Are these normal ranges?

ChevyDave

your temp seems close , maybe +6 but also would depend on outside temp and speed and any hills. so probably

i recorded mine prior to add SC.
drove it 6 minutes out of town onto highway.

temp was about 72 , skys clear, with a/c running but just lightly.
ran for 20 minutes at 70mph... then logged during next 5 minutes (in case slight changes)

engine temp....... 194 to 198
oil pressure........ 41
oil temp............. 217 (climbing ever so slowly)
trans temp......... 127 (blimbing ever so slowly)

2011 GS A6 3lt

Seadawg

Depends on your model, options, and transmission. Tell us more and we can help.

Mad*Max

what year is your car, have you done a coolant flush?

ever since I did my flush it runs at about 200F on the highway (no inclines)

CheeseHeadNinja

Don't mean to hijack this thread but I thought it'd be better to ask here than create another thread.

I just took my 08 out today and it was about 48F outside. I ran at 70mph in 6th gear (about 1500 rpm) for a while and the coolant temp was constantly at ~225F and the oil temp got all the way up to 215F! These seem very hot for just low RPM cruising on a cool day. I can't imagine what it would be if it was 80 or 90F out!

As soon as I slowed down into town and stopped at a red light I noticed the radiator fan was on. Driving thru town the temp kept going up and I got nervous when it was going past 230F so I kicked on the heater full blast and it went down to 220F but oil temp remained at 215F.

These can't be normal temps, can they? What could be the issue? Poor airflow? Old coolant? I was going to do a coolant flush but I can't imagine it would make THAT big of a difference, but the coolant is probably original (5 yrs old). Is a coolant flush hard to do on these cars? I'm not much of a car mechanic but I've done coolant flushes on my motorcycles before.

Mad*Max

the coolant flush made a significant difference in mine for highway driving for sure

vettman96

You may want to check the radiator plenum and make sure it is clear of debris............................

CheeseHeadNinja

Is that a fancy term for "that black plastic jazz underneath the nose"?

Gearhead Jim

Our 2009, and our 2006 before it; both ran coolant right at 195 when cruising the highway at 55-75 mph. Outside temp didn't seem to make any difference, because the thermostat was controlling the coolant temp. Once I get into town and start doing stop & go, the coolant goes to 220 very quickly but very seldom above that (fan).

Oil temp takes a long time to come up, but again 55-75 mph on the highway gives me oil 205-225, depending on outside temp. Oil goes up quickly if i start running the car hard.

Your coolant is supposed to be changed every 5 yrs or 150k (?) miles, whichever comes FIRST. So you are due. A simple drain/refill is easy, but there is a procedure in the Service Manual (don't have mine with me) that is important to use when refilling. IIRC, flushing is not recommended but you might want to do a drain/refill with water only, once or twice, instead of a flush. The lab that tested my coolant strongly recommended using distilled water, even though GM says clean tap water is ok.

CheeseHeadNinja

I think I'm going to schedule a coolant flush with the dealer. I dont want to slop around with that mess, especially this time of year when it'll probably still be cold outside.

At what temp should I start panicing? I still want to drive it a bit this weekend, but is 230F coolant and 215F oil temp a bit too high to be safe? Or am I just getting worried about nothing?

ChevyDave

well, reading your other post, 225 highway cruising is wrong if its 48 out.
if it aint a walmart bag in front of your radiator,
then you really low on coolant or
you disconnected some hoses and introduced lots of air in the system,
something

p.s. i guess we can rule out radiator cap and havent heard of a collasping upper radiator hose for ages

CheeseHeadNinja

Coolant reservoir was full. I'll have to jack it up tomorrow and see if something is blocking air flow.

Boomer111

Or like already mentioned "air pockets".

But something is amiss!

jpee

I just got home tonight 3/29/13 from Atco Drag Strip it was a 150 mile drive , & the outside temp was 51 deg when I left the track after racing.

I set the cruise control to 75 mph and my water temp was 178 deg (I have a 160 T-Stat) my oil was 208 - 215... and my trans (A4) was around 170 - 180

I have a 2800 converter, & an aftermarket trans cooler...in traffic my engine temp will go as high a 197 - 203 deg.. my oil has gone as high as 215 (only when I'm pushing it hard...

Rocketmanwpb

I recently changed my coolant and the engine water temp has remained 198 at highway speeds, sometimes dropping to 196. The oil temp routinley goes to 220 and above, seldom over 225,

LMB-Z

Lay on the floor underneath the very front of the car and look up where the radiator is and see if there is some debris blocking the radiator. Those temps seem very high to me.

CheeseHeadNinja

So it sounds like the oil temp is somewhat normal at 215F?

beaversstonehaven

That is my normal oil temp.....but it takes a while to get there.

2013 LS3

corveteran67

Hmmm, wonder what's up w/my '08 LS3. Even with night driving, outside temp around 80 degrees, my coolant temp reading is 218 degrees, oil temp as much as 239 degrees. Wasn't running that hot until I had the coolant and oil changed at the dealers about a month ago. That's highway driving.

Boomer111

Take the cap off the overflow tank and massage the coolant hose, the idea is to dissipate any trapped air.

If the coolant level drops afterwards you had air.

It is an easy start to trying to remedy the situation.