B5 S4 Stage 3 in South Texas Oil

[nicetie]

Hi all,
I have a 2001.5 Audi S4 with 160,000 miles, it has been tuned to run at 24 lbs of boost and was dyno'd at 442 AWHP and 460 AWTQ. My question is this: Currently I use Rotella T6 5W40 synthetic oil every 5,000 miles, but my oil temperatures have been getting a bit high (for my comfort), considering that during the winter (if it can be called that in south Texas) it was regularly running between 180-200 degrees. However, recently it has been climbing into the 230-250 degree range which has been causing me some concern. Is 5W40 an appropriate viscosity for an entire summer of 100+ degree days? I realize that a stock S4 would probably be OK, but mine isn't quite stock. I was considering going to Castrol Edge synthetic with my next change, but I didn't know if I should stick with the 5W40 or go with something like a 0W60 like what is used in the E60 M5. Thanks!

 

[BrewCityR]

I think it would be interesting to see how oil temps vary with say T6, Belgian Castrol 0w40 and say Mobil1 0w40. Maybe the lighter BC or M1 0w40 would lower your temps.

Cool car btw. I'm considering an '03 RS6 as my next vehicle.

 

[901Memphis]

Nothing wrong with your oil temperatures. Good for burning off contamination.

 

[JAG]

Yeah, 230 to 250 F is not too hot to warrant changing oil viscosity. Cool car!

 

[chubbs1]

This is just a suggestion because the T6 you are running is fine BUT, I would run the oils Brewcity mentioned esp. M1 0w40, it is a fine oil that can be had for a really good price. You just cant go wrong with it. No need to run 0w60 at all.

 

[MBS500]

Does 0w60 even exist? 0w50-yes, but never seen 0w-60.

 

[nicetie]

Sorry, 10W60 is what I meant, 0W60 does exist though.

 

[901Memphis]

I wouldn't freak out until you get close to 300F

 

[dparm]

I wouldn't worry about oil temps until they get up to the 300 range.

I would consider getting a bigger oil cooler though, as long periods of 250 F is certainly not helping anything.

 

[A_Harman]

In south Texas, there is no need to stick with 0wXX oils. 5w or even 10w40 oil would be fine for your highly boosted engine, given the mild temperatures that it will be exposed to for "cold" starts. I'm a fan of RT6 in my Cummins diesel for 24,000 mile oil changes, prolonged towing at 20 psi boost, and the occasional blast at 38 psi of boost. However, I'm not such a fan of RT6 in high performance gasoline engines. I have seen some recent oil analyses on BITOG where it has sheared to a 30-weight.

How much WOT time does your car accumulate?
Do you do track days where the engine will be subjected to high rpm and high boost pressures for more than 5 minutes?

Oil temperatures in the range of 230-250F are of no concern for any synthetic oil. Once you get over 285F and on up to 300+, then you need a really stout synthetic oil. I have seen M1 0w40 oxidize in my Camaro from hard track days. Boutique oils like RedLine 10w40, Motul 300V, or Joe Gibbs DT40 would be best for withstanding long periods at high-rpm, high boost operation. For daily driver, drag race, and autocross use, M1 0w40 would be fine. Pennzoil Ultra Euro 5w40 would be fine, too, if you can find it.

 

[MetalSlug]

A lot high performing shop down here running Mobil 1 5w30 or 0w40 . You should be fine with 0w40

 

[threeputtpar]

Those oil temps are not all that bad, as long as they remain at or below the 250°F mark. I'd say switch to M1 0W-40 or Castrol Edge SPT 0W-40 as they are both on the lighter side of the 40 weight range. I think the RT6 is a bit too heavy for the 2.7t, even when tuned.

I have a stage 1 tune on my 2.7t, and you can see in my sig what I'm currently running for the summer. Next change will be the Castrol 0W-40 and a Mann relabeled Fram filter.

You might be due for a full coolant change. The last timing belt I did, I pulled the block drain at the back driver's side and did a full 7 liter coolant change and my oil temps dropped 15-20°F. They now hold steady at just over the 200°F mark on the gauge and don't really move no matter how much I flog the car.

Oh, and I hope that your S4 is a 6-speed. I don't think that the 5HP19FLA can handle that amount of power for any period of time.

 

[threeputtpar]

Originally Posted By: BrewCityR
I'm considering an '03 RS6 as my next vehicle.


I've been thinking the same thing, but then I look at my checking account balance and think that I like to hang on to my money and the thought of an RS6 goes away for a while. But it shure would be fun to have one for a couple of weeks.

 

[nicetie]

Originally Posted By: A_Harman
How much WOT time does your car accumulate?
Do you do track days where the engine will be subjected to high rpm and high boost pressures for more than 5 minutes?


I have only taken this car to the track (drag strip) once, however I do have a VERY heavy right foot, and I go WOT pretty often, but only in short bursts (i.e., to highway speeds) I have no plans on accumulating much more track time in this car, I never really liked drag racing as it's really hard on driveline components, and it's my DD, so I need it to work consistently.

 

[nicetie]

Originally Posted By: threeputtpar
You might be due for a full coolant change. The last timing belt I did, I pulled the block drain at the back driver's side and did a full 7 liter coolant change and my oil temps dropped 15-20°F. They now hold steady at just over the 200°F mark on the gauge and don't really move no matter how much I flog the car.

Oh, and I hope that your S4 is a 6-speed. I don't think that the 5HP19FLA can handle that amount of power for any period of time.


I've had the timing belt replaced within the last 15,000 miles but I think I have a stuck thermostat so I'll be doing that again soon. And yes, it is most definitely a 6-speed lol. I wouldn't dare put that kind of power through the garbage "tiptronic" transmission.