Hi everyone. I recently replaced my thermostat & water pump. See this thread for that discussion: https://dodgeforum.com/forum/3rd-gen...-7-100k-2.html

I gave it a 50/50 mixture of Dex Cool/Distilled water and worked the air out of it.

The thermostat was from Napa and is a fail safe version (if it fails, it fails open). Rated @ 195 degress.

I hooked up a bluetooth OBD II reader to watch coolant temperature and watched it (what the ECM was reporting) as I took the boat to the lake (12-1300 lbs). I hit a max temp of 219 while going up Ute Pass (4-5% grade about 5 miles long). Ambient temperature was about 75 degrees. I've never watched my temp that closely before, so I'm not sure how it would have behaved with the old t-stat, this could be normal. Normal level driving seems to maintain 204-210 (even while not towing). I was running the A/C at that time btw. Looking at the idiot gauge, the truck was happy, though it showed a slight elevation above normal temperature.

I'm not sure what temperatures to expect, or specifically when it's time to worry. I'd like to hit worry before I hit something intolerable and have always been told not to trust the gauges.

Truck is a 2008 Ram 1500 SXT Quad Cab 4.7. Transmission has the O/D off and Tow/Haul settings. I was using tow/haul while pulling up the pass.

Thanks

 

Why do you think it isn't working? The normal average temperature of a running engine is 195-220 degrees. Your truck is perfectly normal. You would expect the high end of normal at load and mid level a normal workload. Your truck is perfect and now you know your idiot gage works good and you can trust it.

 

Thanks, I appreciate the feedback. I didn't know it wasn't working, but I never did know what normal was.

Thanks again.

 

Now that you know your engine temp gauge works good, I'd recommend you monitor your transmission temp with your scanner. Tranny temps will normally be around 200, and you may see 230 or so towing through hills.

 

That's a good idea. I don't see that feature on my device, but I'm sure I can find another that would do it.

Thanks

 

always put in a 180 degree f. thermostat.. the stock 196.f is just for smog . I put in a 180 and my temps dropped a lot 7 years ago.. I now have 365,000 miles on the engine. and passed smog everytime with the 180 in.
cheapest upgrade you can do.

 

I did that a long time ago with my 88 suburban. Is that still advisable? Would it require reprogramming of the ECM?

 

According to theory, the PCM will whine about Engine too cold too long.... But, that seems rather hit or miss. Some trucks seem much more sensitive to it.

 

400,000 original miles with a 180, never got any codes. at least on gen 3 you don't.......not sure about gen 4 .been in zero degree temps to 120 degree temp .. everything seems the same, just ran cooler when fully warm.
the only reason the stock opens at 197 is because your supposed to get more fuel burned in the cylinder the hotter it is. which results to less smog. I don't notice any difference and i still passed smog.
to me the damage from the heat long term is not worth it. I will get half a million miles out of my hemi I'm sure.. doesn't even burn oil at 365,000 miles and has good compression..

 

OP has a 4.7L. The combo of electric and clutch fans are quite sufficient at cooling the engine. I wouldn't suggest deviating from engineer's intended temp on those as you might end up with sludge. Ever look down into the oil filler cone on a 4.7 during winter? Lots of yellow goo and that's with 195/196 stat'.