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Old 12-30-2013, 09:43 PM
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Waste_Gate Waste_Gate is offline
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Join Date: Mar 2013
Location: Chapin, SC
Posts: 130
Quote:
Originally Posted by Brian Carlton View Post
When I worked for Chrysler, they had a Diplomat running at 235F. with a high pressure cooling system. It got about 15% better fuel economy than the standard vehicle.

Never decided to go forward with a prototype vehicle because of durability and maintenance issues.

Suffice it to say...........the warmer you run the engine, the better the fuel economy.
This relates exactly to the lower mgp's I've been getting since winter started. I'm pretty sure my thermostat is partially stuck open. Last summer I only had to fill up about once every 4 weeks. At that time, I was reaching 85 degrees every time I was driving in the city. Since winter, I've been averaging about 75 degrees and have to fill up about every three weeks now.

I'm a constant gauge checker and last summer I always maintained 85 to 90 degree coolant temp on the interstate but this winter, I can only max at 85 and when I go from 80 mph in the interstate to 60 on back roads, it quickly drops to about 75 degrees, sometimes down to 70 (ambient temps of about 50).

I have a new 85 degree Behr thermostat and am about to install it with some zerex. I'll let ya'll know what effect this has on MPG. FWIW, I thought my temp gauge was inaccurate so I hit the thermostat housing with the IR gun and it was close to the gauge temp, then I ohm'd the temp sensor on the head and it matched the gauge so I know the gauge is reading correctly.

Willson,
85 300CD
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