Canadian Hummer Club Forums

Just a question...seeing as how it's really cold (It's in the -30degrees where i am), I was wondering if it makes sense to cover up the radiator to block the cold air from cooling the radiator/coolant flowing through it so that the vehicle stays warm and keeps the cabin somewhat 'more' warm. Ive seen big trucks and busses with diesel engines do that. They partially block the radiator with cardboard.


I have a block heater plugged in when the truck is parked outside...so that helps with cold start


I've read that Diesel engines produce less heat than regular engines, and the incoming cold air against the radiator can make it even cooler, making it difficult to keep the cabin warm...not sure if there is any science or truth behind that theory.


Has anyone done it. if so, which should I cover up...the front or the grill on the hood Or both?

Personally I start like 15 or so mins early (remote starter) and let warm up with rear heater on full blast,

I shut off outside air while warming up, (added vacuum switch to hvac)

So heat blows hard. Don't drive like that or windows fog ....fast,heheh

Never needed to cover rad, but I hear ya, some days, truck gets angry cranking over when mega cold, hehe

But ya imo if she warms up good, will stay warm,

If you drive a lot in the winter, YES, You should cover the radiator.

It is not that diesels produce less heat, it is that they have cooling systems that are double to triple the size of a Gas engine! By doing this you will help the engine to get to operating temperature which will help two things...

1. Provide youi with Heat Inside the passenger area!

2. Keep your engine happy! A cold engine is not an efficient engine and if you can't get to operating temperature you will get condensation in your engine which will make you oïl look like very creamie coffee.

I always had my rads covered on my diesels...It really does make a big difference!

How about gas engines? What do you think, guys, about H2? I've never seen before H2 with covered radiator- front grill.

If you drive a lot in the winter, YES, You should cover the radiator.


It is not that diesels produce less heat, it is that they have cooling systems that are double to triple the size of a Gas engine! By doing this you will help the engine to get to operating temperature which will help two things...


1. Provide youi with Heat Inside the passenger area!


2. Keep your engine happy! A cold engine is not an efficient engine and if you can't get to operating temperature you will get condensation in your engine which will make you oïl look like very creamie coffee.


I always had my rads covered on my diesels...It really does make a big difference!

Do u cover the hood radiator stack or the grill on the front.

Do u cover the hood radiator stack or the grill on the front.

You will need to cover both. There was a kit from AM General to be able to do it.

How about gas engines? What do you think, guys, about H2? I've never seen before H2 with covered radiator- front grill.

Not a neccesity on the H2...we have a little Under half the coolant in our system compared to the diesel trucks and even when I have been on long trips up North to Chicoutimi in -40 I have never found a need for it on our trucks.

Today,guys, I really feel that it's a good idea to cover not just radiator, but whole truck with some warm blankets!

I agree, even my 2013 dura max did not start. had to plug it in, then once half warm, fuel lines seemed to be frozen.... did not want to run or rev for a couple minutes, finally got it going.
BTW the front blanket does not help on initial startup!!!! Who knew?    

Wow , I just looked at Ont. weather, we had +12 yesterday and + (very sunny) 11 today,

I do not miss those temps you have today.....wow