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?
Should we cover the radiator in winter...say below -20degrees
- Skenth
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Should we cover the radiator in winter...say below -20degrees
Sonny Kenth
96 Hummer H1 4 dr Hardtop w slantback
96 Hummer H1 4 dr Hardtop w slantback
- Monk
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Re: Should we cover the radiator in winter...say below -20degrees
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,
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,
Last edited by Monk on Fri Feb 13, 2015 10:35 pm, edited 1 time in total.
96 HMC4
Optimizer N/A
Super Swamper IROKS 39.5x13.5x 16.5
Optimizer N/A
Super Swamper IROKS 39.5x13.5x 16.5
- whitehumh2
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Re: Should we cover the radiator in winter...say below -20degrees
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!
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!
<p class="bbc_center">1 - There is a time for everything,
and a season for every activity under the heavens:
3b - a time to tear down and a time to build,
5 - a time to scatter stones and a time to gather them,
Ecclesiastes 3:1,3b&5a
and a season for every activity under the heavens:
3b - a time to tear down and a time to build,
5 - a time to scatter stones and a time to gather them,
Ecclesiastes 3:1,3b&5a
- collega
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Re: Should we cover the radiator in winter...say below -20degrees
How about gas engines? What do you think, guys, about H2? I've never seen before H2 with covered radiator- front grill.
Hummer,like nothing else!
- Skenth
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- Joined: Tue Jun 04, 2013 10:59 am
- Location: Milton, ontario
Re: Should we cover the radiator in winter...say below -20degrees
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.
Last edited by Skenth on Sat Feb 14, 2015 3:26 pm, edited 1 time in total.
Sonny Kenth
96 Hummer H1 4 dr Hardtop w slantback
96 Hummer H1 4 dr Hardtop w slantback
- whitehumh2
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- Joined: Tue Jul 04, 2006 11:47 pm
- Location: Lachine, Quebec
Re: Should we cover the radiator in winter...say below -20degrees
You will need to cover both. There was a kit from AM General to be able to do it.Do u cover the hood radiator stack or the grill on the front.
<p class="bbc_center">1 - There is a time for everything,
and a season for every activity under the heavens:
3b - a time to tear down and a time to build,
5 - a time to scatter stones and a time to gather them,
Ecclesiastes 3:1,3b&5a
and a season for every activity under the heavens:
3b - a time to tear down and a time to build,
5 - a time to scatter stones and a time to gather them,
Ecclesiastes 3:1,3b&5a
- whitehumh2
- CHC Trail SuperGuide
- Posts: 4529
- Joined: Tue Jul 04, 2006 11:47 pm
- Location: Lachine, Quebec
Re: Should we cover the radiator in winter...say below -20degrees
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.How about gas engines? What do you think, guys, about H2? I've never seen before H2 with covered radiator- front grill.
<p class="bbc_center">1 - There is a time for everything,
and a season for every activity under the heavens:
3b - a time to tear down and a time to build,
5 - a time to scatter stones and a time to gather them,
Ecclesiastes 3:1,3b&5a
and a season for every activity under the heavens:
3b - a time to tear down and a time to build,
5 - a time to scatter stones and a time to gather them,
Ecclesiastes 3:1,3b&5a
- collega
- CHC Pilot
- Posts: 191
- Joined: Fri Feb 12, 2010 10:56 pm
Re: Should we cover the radiator in winter...say below -20degrees
Today,guys, I really feel that it's a good idea to cover not just radiator, but whole truck with some warm blankets! 

Last edited by collega on Sun Feb 15, 2015 2:58 pm, edited 1 time in total.
Hummer,like nothing else!
- Roy
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- Location: Stratford,Ontario
Re: Should we cover the radiator in winter...say below -20degrees
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?

BTW the front blanket does not help on initial startup!!!! Who knew?


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5.9 Cummins 12 valve mech. Stocking most parts to fix your H1

41.5-13.5 R16.5 Pitbull Rockers,
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Full custom underbody protection
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12100 rear cv shafts
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<p style="text-align:center;"> 
- Monk
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Re: Should we cover the radiator in winter...say below -20degrees
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
I do not miss those temps you have today.....wow
96 HMC4
Optimizer N/A
Super Swamper IROKS 39.5x13.5x 16.5
Optimizer N/A
Super Swamper IROKS 39.5x13.5x 16.5