The best engine block/oil heater for diesel engines (that is also moderately) priced is a stick on type that is made by Wolverine Heaters.
If you want the quick answer: the specific model that’s best is the Model 80 1000 Watt Fluid Heater (120 Volt). You can find it on Amazon by going here.
For those of you that need a little more information before you buy one please keep reading about my experiences with this heater.
In this article I’m going to tell you about my experiences with the Wolverine Model 80 stick on heater while helping a cousin maintain his small fleet of tractors (4) in the Chicago area.
Note: all of the trucks were for local driving only, they were all day cabs. We had access to outlets that we could plug them into every night but if you are driving OTR you probably won’t.
Keep in mind that these engine heaters can work in any car or truck, not just commercial vehicles. For more information about Wolverine Heaters click here to go to their website. They have a heater for just about any type of vehicle.
First Impressions
I’m not afraid to say that at first I was hesitant to buy one because it looks a lot like a heating pad that I use in my bed to keep warm. I didn’t think it would last very long.
After receiving it I changed my mind because the build quality was pretty darn good. My cousin and I decided to buy 4 of them and try them out.
Did I expect that this thing was going to last 10 years? No. But I was hoping to get 3-5 years out of it while mostly driving throughout the Chicago area as well as NW Indiana. Winters up here can get pretty cold.
I did like how easy it was to install (more about that later) and it came with some fairly easy to understand directions though it would had been a little better if there were some diagrams or pictures to help with the installation. Not a big deal though.
Take a look at the installation guide for yourself by clicking here.
I did notice that it was made in the USA which for me was a bonus and it came with a 2 year warranty.
Tips For Installing The Oil Heater
Like I said earlier the installation for the heater was not too bad. Overall I think it took me about an hour to do each one.
I’m the kind of person that likes to take their time (not a perfectionist though) so that things get done correctly.
Here are some tips that will help you with your install:
1. The heater comes with an installation kit which included plastic zip ties, a tube of high temperature silicone sealer, and a plastic scraper. No need to buy these things.
2. Make sure the surface you are putting it on is as flat as possible. My oil pan was not totally flat so I had to use this Strong Steel Stick to fill in some low spots. This is the stuff that the company recommends using.
Not having a flat surface means it will have uneven adhesion and heating so make sure you get it as flat as possible so it has more surface area to stick to.
3. Don’t install on a cold surface. The surface you are putting the heater on should be warm. I did my install in August when the temperatures in Chicago were in the 80’s.
4. Regarding the surface you are installing it on: It has to be clean and completely dry. You will have to get rid of dirt, oil, and grime ahead of time. The recommended liquids for this are acetone, Brakleen, or a strong detergent followed by a good rinse.
Now the things you should NOT use: Gasoline or Diesel fuel, spray penetrants, or solvents.
I used Brakleen and then washed the oil pan down with Simple Green and gave it a good rinse. After that I dried it off completely. It has to be completely dry before you stick the heat pad onto the oil pan.
5. Plug in the warmer for a few seconds to warm up the adhesive before putting it on the oil pan. I do mean a few seconds, these things heat up fast! Don’t plug it in for more than 5 seconds. Doing this softens the adhesive too much.
How Well Did The Heater Work?
It worked pretty well. They were plugged in whenever the temperatures got really cold and eliminated cold starts.
We didn’t have anymore clouds of smoke in the morning as the drivers were warming up their trucks.
I’m sure that starting the trucks with warm oil is definitely going to reduce wear on the engine too.
For the relatively low price this heater is has a good return on investment. If the engine lasts a few more years then the money spent is well worth it.
How Long Did They Last?
They didn’t last as long as we thought they would. I thought we would be able to get about 5 years out of them but they usually only lasted 2-3 years.
Actually, here is out data:
2 heaters lasted between 2 and 3 years
1 heater lasted 3.5 years
1 heater lasted 4 years
Not bad. Since then we have bought some new heaters and are going to be installing them again.
What Do Engine Oil Heaters Actually Do?
They heat oil!
This is good because when you startup the engine there is warm oil that moves through the engine right away. It’s actually a really simple concept. Warm, fluid oil is pumped throughout the engine right away instead of cold, sludge like oil not being pumped right away.
This is why/how they are able to increase engine life and battery life too.
Benefits Of Using An Engine Oil Heater
Like I said earlier the heater keeps the engine oil warm which will reduce wear at startup during those really cold winters.
Another benefit is they reduce warm up time for drivers. There are some environmental benefits too. Heaters can extend oil life and lower noise emissions.
Should You Get An Engine Heater For Your Semi Truck?
I would. For such a small investment they really work well. Just don’t expect it to last a long time. I would say somewhere between 2-3 years seems normal based on my experiences.
Other Types of Engine Oil Heaters?
Stick On Pad Heater: This is the type that my cousin put on his 4 trucks. They are really easy to install using the adhesive that comes on the heater. Just make sure the surface you are putting it on is as flat as possible and get it as clean as possible.
All you have to do is stick in on the bottom of the oil pan and plug it in and you have warm oil at startup.
Dipstick Heater: The dipstick heater replaces the oil dipstick with a coil that heats the oil directly. I have never installed one of these but I imagine it wouldn’t be very difficult.
I looked around a little and discovered that all you have to do is remove the dipstick, put the dipstick heater in place of it, and turn it on. Definitely worth trying out at some point.
Engine Warming Blankets: Basically a large heat blanket that you put over the top of the engine or attach to the inside of your hood.
These might be okay in some situations but we wanted something that directly heated the engine oil. These warming blankets limit the heat to the top of the engine, never reaching the oil in the oil pan.
Magnetic Warmer: These are attached via a magnet or several magnets and then plugged into an outlet. They seem okay in that they directly heat the oil but I’d worry that
they would fall off.
This (Amazon link) is an example of one that I found but it’s only 300 Watts. That means it will heat about 20 square inches of oil. Way too small for a truck, probably better suited for cars or pickups.
