1994 Dodge Ram Heating problem

jmw642

Have a 1994 Dodge diesel . Have had it for the last 20 years and am still having a problem with the motor temp. It will heat up to 185 then drop down to 145. Then work its way up to 185 then drop back to 145. Have changed to thermastate 4 or 5 times with no change. Runs just fine but will not keep a costant temp. Any ideas out there.

KCRam

My 1996 Cummins was like that the whole time I had it. It's not anything wrong; it's a function of the engine. A mechanically-controlled diesel is extremely efficient and will actually cause that cooldown you're seeing. This is why diesel owners are always told to be sure to keep a decent load on the engine. The newer computer-controlled engines keep a more constant check of the engine's performance and adjust on the fly to keep the temperature at an even level.

jmw642

thank you was the first I have gotten an answer for the temp. You would think the dodge guys would know it plus actually went to Dodge an there answer was a different therostat which did work for about 50 miles then back to the same . Thanks again will just let it do its thing.

takumi_

Does it cool off once you get moving? Try a grille cover/blanket or ghetto cardboard to reduce the outside airflow to the rad during colder outside temps. Don't seal it off, just keep the rad warm, It's cheaper than keeping a load on the motor.