Auxiliary Engine oil cooler


After owning and working on Sprinter vans for the past 10 years I developed an Engine oil cooler kit for them to combat the overheating of the engine oil. The Sprinters suffer from a heat exchanger that was not designed big enough for the loads we put the vans under with all of the weight from the RV conversions or towing.
I developed this kit because I had engine failures and shortened life due to engine oil overheating.
I have tested the kit for 4,000 miles in the Arizona, California, and Nevada heat.

The kit is a complete bolt on kit with the Oil filter adaptor housing, Remote oil filter, Cooler, Cooler brackets, 5/8" hose (AN10), and AN hose fittings.



New member
Very cool. I noticed that my engine oil temps get pretty high when going over mountain passes - where the turbo is probably spooled up pretty good for a long period. Are you selling as a kit?


2012 NCV3 3500
How much extra oil capacity is added by your kit?


What kind of temp reductions are you seeing with your cooler?
15-30* depending on outside temps. When it is 100* outside and climbing a considerable grade trying to stay at 80mph you only have a 15* reduction from one set up. But if you slow down to 60-70 you get a better temp reduction.


Well-known member
To check this you need to use scientific calibrated thermo couples inserted into the system plotting temperature rise curves , .stabilization, etc etc .
If I was to present this to the chief engineer where worked doing engine repowers I would get laughed out the bloody building.

To present your product you need to present more than this !
In short an engineering study with some REAL data .
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I am currently on the road. These are pics to show what the owner can expect to see on the dash gauge. Both pics are taken on the same day. On the same grade. One with the cooler hooked up. The other with the cooler disconnected.
98* 11,000 lbs rv conversion 4x4 3500 dually. Traveling up Cajon pass on I 15 in Southern California.
I have more specific data from inline gauges for data collection.
I understand your point and agree that more specific data is useful while developing. But 90% of end users don’t understand the data presented to them and end up not reading it.


2018 144" Tall Revel
Just spitballing here......But it seems to me that a transmission oil cooler would be a better way to lower temperatures in general.
Or rather, adding a transmission cooler would be a way to stabilize all three temperatures......Coolant, transmission fluid and oil.
Because the transmission puts quite a load on the radiator. And hot coolant doesn't cool the oil.
The other issue with adding an oil cooler to the engine is that it will keep the oil temp too low in cold weather.
At least with a transmission cooler, the coolant will heat the transmission in cold weather.


The newer sprinters already have a decent sized trans cooler. Max temp in the trans I have had is 200 while towing in 100* weather.
the engine oil is also temp controlled by the stock heat exchanger and the engine coolant.
For reference. The sprinter engine oil runs much warmer than any diesel powered Ford,Ram, GMC truck.

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