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MacDR50
03-19-2010, 12:10
LMM engine with winter cover on and temps around 35-45F. On occasion the tranny temp climbs to about 80C, the temp gauge for the engine stays at 100C (not sure how accurate it is) and the outside temp indicator (now behind the front cover) gets up to 30C. Can smell the rubber and oil. I am driving highway sppeds when this happens. It seems to be associated with the DPF regen but I am getting worried that I may have a sticky thermostat or some other issue. Dealer's service counter system is a PITA and my next service is still a ways away. Will a hot engine throw a code? Any thoughts that might help are welcome.
npauli
03-21-2010, 19:16
I'd say take off at least the bottom cover, or both to be safe.

With my LB7 & both covers on, underhood air (but not coolant) temps get too high under light use whenever its ~ 50-60F or higher out. With just the top cover on, I haven't seen any temps getting too high @ similar temps. I like using just the top cover since it gives most of the warmup & mpg benefits of both covers without as much risk of getting too hot.

LMM is probably a bigger source of heat than LB7, from EGR & DPF regens, so you'll probably have to take covers off at a cooler temp than I would. YMMV
DmaxMaverick
03-22-2010, 08:10
You shouldn't be covered at any temp above freezing (0/32), and in most cases, much lower than that. Once you install the covers, disregard the "outside temp" indication, as it's now useless (it's the air temp between the cover and cooling stack, which tells you nothing). As suggested, at least remove the lower cover until you need to warm up in much lower temps.
MacDR50
03-23-2010, 12:07
Thanks for the responses. Cover is now off and I am inclined to get an aftermarket one. The stock cover is a PITA to put on and take off. Anyone know of a good one that allows adjusting the openings?
jbplock
03-23-2010, 16:48
Anyone know of a good one that allows adjusting the openings?

Try http://www.cloud-rider.com .. I've had one for my 03 since new (http://rides.webshots.com/photo/1103356739033933568mpWojf)- very pleased .. I put in on in the fall and take it off in the spring when temps rise above 50F.

:)
npauli
03-23-2010, 18:55
FWIW,
Supposedly GM's working on active louvres in the grill that open and shut automatically to get the best balance of fuel economy, warmup, aerodynamics, and temperature control.

That would be nice.
JohnC
03-25-2010, 11:49
Five winters in upstate NY and central NH and I have yet to put the cover on...
Mark Rinker
03-25-2010, 17:43
FWIW,
Supposedly GM's working on active louvres in the grill that open and shut automatically to get the best balance of fuel economy, warmup, aerodynamics, and temperature control.

That would be nice.

Awesome idea. I have arrived at rarely running the winter front up here in MN, this year I never did put it on. Reason? Exactly what you have pointed out here...the need to block airflow is dynamic. For quick warm-ups you need it, as soon as you hook onto 10K# of steel to deliver, even on a cold MN day, you want it off again...

I would rather waste the fuel with too-cool underhood temps, than risk the problems associated with too-hot underhood temps.
MacDR50
03-30-2010, 12:36
It is off and will stay off. I like the louver idea for those mornings when it is really cold. My problem is I am close to work and without the cover I just never warm up. It is not unusual to see a double digit change in temperatures during a 24 hr period and the GM stock cover is a PITA to remove and put back on. I need to locate a cheap car :mad:
npauli
03-31-2010, 14:57
I like the louver idea for those mornings when it is really cold.

coming soon....
To a Chevy Cruze near you

http://green.autoblog.com/2010/03/31/2011-chevrolet-cruze-eco-new-york-2010-reveal/



Starting with the front of the Eco, there's a new, wind tunnel-massaged front fascia complete with a class-first "Aero Shutter." Take a look at the air inlet area below the grill. During low speed driving (say stop and start city type stuff) the aero shutter is open. However, at higher speeds when cooling the turbocharged engine isn't as much of an issue, the shutter shuts, allowing air to more efficiently stream around the vehicle.


So when can I get an aftermarket grill that does the same thing for my Dmax?