It's been fairly cold here the past couple of days... close to -20C (0F) and I've noticed that immediately after starting my rig, the RPM's instantly go to 1000. Normally, they're supposed to be 700rpm for about 2 minutes before the cold idle kicks in and brings them up to 1000. I'm just wondering if this might be extra hard on the engine or if it's not really a big deal. I just had the G30 flash 2 days ago and this started happening the next day. All answers and opinions would be appreciated!

 

Mine does the same thing when it's cold. I just got back from Colorado and it seemed like when it was around 15f it would go right to 1000rpms, but when it was around 20f or so it would idle for a few minutes and then up to a 1000. I don't think it hurts too much, it doesn't seem to rattle or make any awful noises.

 

They all do that.My 03 does.Chicken house generators near me are what look like big Detroit diesels.They start up once a week as a test and to keep them lubed etc.They go from off to govened wide open in 2 seconds all year round!

 

Same here! Hadn't been that cold around here to do it, but was is Iowa last weekend and it did it every morning. Back here in Indiana, and above the single digits that Iowa had, it has been normal.

 

Being your in Canada and it does get a bit cold up your way I would make sure you have good synthetic oil in your engine. Be sure that your oil has a pour point of no less then -44 C/-47 F in it so that you have good oil flow at start up. Lack of good oil flow at start up is hard on your engine.

My02

 

Thanks for all the feedback. I just wanted to be sure that I'm not damaging the engine by having it rev higher than 700 rpm as it states in the owner's manual.

I'm currently running Unocal's Guardol 15W40 ECT CJ4 rated semi-synthetic oil. The lube tech where I work says that it has a pour point of -44C. It actually has the exact same specs as a 5W40. At $12 a gallon, it's a good oil at a good price. Even at -10F (the coldest it's been so far this year), the oil pressure comes right up on startup.

 

dodgeram_dude,

I'm surprised that your using 15w40 oil and not 5w40 oil in the cold temps you have up your way. IIRC Dodge recommends to use 5w40 synthetic oil when temps are below zero. I know you said the oil you use has a good pour point but I would think that 5w40 synthetic oil would flow better in cold temps then 15w40 oil does.

 

The Unocal 15W40 I'm using now is every bit as good as a 5W40... same pour point, same flow rate. It could in fact be legally sold as a 5W40. The main reason it isn't is that many of the heavy truck/fleet operators would never buy it if they thought it was a 5W40. All they ever use is 15W40 so it is marketed as such. My rig starts like it's +20C out there... no hesitation whatsoever. As has been pointed out countless times on many threads, each individual has their own theories and beliefs on what brands are best, synthetics vs conventional, etc. In many if not most cases, these oils have the exact same additive package. Only the marketing sets them apart.