Coming home from Arkansas with a 37 footer behind me, my truck began to run hotter than normal. (about 2 to 3 needle widths above 190 but in side the operating range) I stopped and blew out the radiator at a car wash... ... ... no help. So..... one eye on the road and one on the temp. guage, I came on home. In talking with my tech/mech the next day he immediately said "thermostat". I called the parts dept. at the Dodge store and asked for a thermostat for a ETH Cummins. The man said, "I have 4 in stock and they are all the NEW STYLE". My mech/tech told me that Cummins has been having a problem with the thermostats coming apart... ..... hence the new style has been introduced. Anyone else had a problem????????
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Do we have a thermostat problem???
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Houston, we have a problem: Just pulled the themostat out and it is split wide open across the dome. The part that is really scarry is that the one Dodge sent me is just like the one I took out. I am going to drop by the Cummins store and see if they have one that is differant... ... ... ... ... Y'all be careful!
Shooter
TDR MEMBER
They are about $17 at Cummins
I have been through 4 in the last 35k mi. THe original would hold 190 up hill, down hill, at 100+* and down hill at 20* ambient. Unfortuneatly it was replaced when I got my new short block at 10k mi. The next 3 have not been able to hold 160 down hill in summer and in winter will barely get to 160 towing. They will also allow water jacket temps to reach 220 while pulling long grades. I am hoping to get another good one eventually. The last one had a new rev # but still does not hold temp.
I have been through 4 in the last 35k mi. THe original would hold 190 up hill, down hill, at 100+* and down hill at 20* ambient. Unfortuneatly it was replaced when I got my new short block at 10k mi. The next 3 have not been able to hold 160 down hill in summer and in winter will barely get to 160 towing. They will also allow water jacket temps to reach 220 while pulling long grades. I am hoping to get another good one eventually. The last one had a new rev # but still does not hold temp.
No, I do not deal with Hooks. I have not had a service problem to take it to the dealership. My truck has not run warm or hot until this thermostat came apart. Going to do a PHX. turn around this weekend to pick up a 32' Jayco Designer 5th wheel. If I have any problems with this new thermostat, I was a medic in Vietnam, I'll do a thermostat-ectomy... ... ... ... ... ... ... ...
Is this a problem for the 2001s? My 2000 is still working fine, with 35,000 miles on it. It appears by your sigs, that you're all 2001 owners.
Doc
Doc
At what temperature is overheating? Last week I was pulling 6k#
@2200 r. p. m. through Oklahoma and Kansas with outside temps
up to 110 degrees. The temperature gauge was about 2 or 3
needle widths above 190 but I did'nt think too much of it because
of the conditions. I did notice the fan clutch cycling more than normal though. Should I be concerned? Also what kind of m. p. g.
should I expect under these conditions? I've been averaging about 12-13.
Thanks.
@2200 r. p. m. through Oklahoma and Kansas with outside temps
up to 110 degrees. The temperature gauge was about 2 or 3
needle widths above 190 but I did'nt think too much of it because
of the conditions. I did notice the fan clutch cycling more than normal though. Should I be concerned? Also what kind of m. p. g.
should I expect under these conditions? I've been averaging about 12-13.
Thanks.
Dunno what a 12Ver can offer, but the motors are fairly similar.
For about 60K miles, the gauge stayed around 180 or so in the summer. Then it started climbing up quite high when hot outside. The cab heat would vary by at least 20 degrees, summer and winter. The A/C would not work much in the heat in slow city driving, and barely work at highway speeds. Also, I finally realized I hadn't heard the fan run in months. So I bought a new clutch, figuring to install it myself. Fat chance!
When I brought the truck in to Cummins Atlantic for a 90K tuneup, they found the engine temp getting up to 230+, while the radiator stayed kind-of cool. The t-stat was 'sticking'. Then they found the fan clutch wouldn't engage until over 220. So I had them install the clutch. It was still getting hot and suggested I get the radiator rodded out, but I said I'd drive it and see how it was. They also adjusted the top end and spillport-timed the pump. And replaced the rad cap which was leaking.
I later had an A/C service shop checked the A/C, as it stopped working the instant I left Cummins. Turns out the PCM decided to stop telling the A/C to turn on. I told him to wire it direct to the relay. He also charged up the A/C; it was a little low. (I need to check the IAT sensor; if it's telling the PCM it's frigid outside, that might be the problem. But maybe not, since I haven't heard the heater relays clicking on this summer. )
Bottom line, in my recent drive from SW VA to SW MN and back, the temp stayed under 190 and it was much more stable, especially running 80 MPH up a 7% grade at 90 degree ambient temp. The A/C worked better than it has since the day I bought the truck, on highway and in city. And I now hear the fan running when needed.
So, if you haven't heard your fan run in a while, you may need a new fan clutch. If your engine temp is climbing over 190 or so, you may need a t-stat. And if you have over 50K miles, replace the rad cap on principle.
Fest3er
WARNING! 12V-specific INFO FOLLOWS!
The other adjustments seem to have gotten my mileage up to 19-19. 5 at 70-75MPH. Cummins say I have 172 HP @ 2500 RPM according to their RW dyno; I'm told that's pretty good for a 2500 auto.
(I need to change my sig. I do have 215HP injectors, K&M filter, Amsoil throughout and a JRE 4" turbo-back exhaust. Just a few 10 lb. bombs, none of those 100 kiloton bombs some of you have!)
For about 60K miles, the gauge stayed around 180 or so in the summer. Then it started climbing up quite high when hot outside. The cab heat would vary by at least 20 degrees, summer and winter. The A/C would not work much in the heat in slow city driving, and barely work at highway speeds. Also, I finally realized I hadn't heard the fan run in months. So I bought a new clutch, figuring to install it myself. Fat chance!
When I brought the truck in to Cummins Atlantic for a 90K tuneup, they found the engine temp getting up to 230+, while the radiator stayed kind-of cool. The t-stat was 'sticking'. Then they found the fan clutch wouldn't engage until over 220. So I had them install the clutch. It was still getting hot and suggested I get the radiator rodded out, but I said I'd drive it and see how it was. They also adjusted the top end and spillport-timed the pump. And replaced the rad cap which was leaking.
I later had an A/C service shop checked the A/C, as it stopped working the instant I left Cummins. Turns out the PCM decided to stop telling the A/C to turn on. I told him to wire it direct to the relay. He also charged up the A/C; it was a little low. (I need to check the IAT sensor; if it's telling the PCM it's frigid outside, that might be the problem. But maybe not, since I haven't heard the heater relays clicking on this summer. )
Bottom line, in my recent drive from SW VA to SW MN and back, the temp stayed under 190 and it was much more stable, especially running 80 MPH up a 7% grade at 90 degree ambient temp. The A/C worked better than it has since the day I bought the truck, on highway and in city. And I now hear the fan running when needed.
So, if you haven't heard your fan run in a while, you may need a new fan clutch. If your engine temp is climbing over 190 or so, you may need a t-stat. And if you have over 50K miles, replace the rad cap on principle.
Fest3er
WARNING! 12V-specific INFO FOLLOWS!
The other adjustments seem to have gotten my mileage up to 19-19. 5 at 70-75MPH. Cummins say I have 172 HP @ 2500 RPM according to their RW dyno; I'm told that's pretty good for a 2500 auto.
(I need to change my sig. I do have 215HP injectors, K&M filter, Amsoil throughout and a JRE 4" turbo-back exhaust. Just a few 10 lb. bombs, none of those 100 kiloton bombs some of you have!)
Looks like the same problem I had with my '99. There is a TSB covering the problem - I don't remember the number. I got the "revised" part after mine broke at 7,000 miles. Have 55,000 now and no problems yet. When I changed mine, I gained 2 mpg. Don't forget to change your coolant once EVERY year - critical to diesels.
Overheating
My son and I have twin trucks bought on the same day. Except his is stock-no bombs.
He hauled three horses in a pull behind to the Bob Marshall Wilderness last week and the dodge started to run hotter going up the divide out of Helena, MT. He came home through Butte and run the divide in 3rd locked up to keep it from boiling. He could run 45mph without getting it too hot. Dropped the horses off in Bozeman but even with less weight it kept getting worse, but he made it home.
We just pulled the thermostat, put in a pan of water with a thermometer. It was still closed at 190 degrees, but opened about an eighth of an inch at 200 degrees. Thats as far as it ever opened and the water was boiling then. Our altitude is 3800ft.
Cummins in Worland says they will have us two thermostats tomorrow. I will boil them and see, but I know an eighth is not enough opening.
My son and I have twin trucks bought on the same day. Except his is stock-no bombs.
He hauled three horses in a pull behind to the Bob Marshall Wilderness last week and the dodge started to run hotter going up the divide out of Helena, MT. He came home through Butte and run the divide in 3rd locked up to keep it from boiling. He could run 45mph without getting it too hot. Dropped the horses off in Bozeman but even with less weight it kept getting worse, but he made it home.
We just pulled the thermostat, put in a pan of water with a thermometer. It was still closed at 190 degrees, but opened about an eighth of an inch at 200 degrees. Thats as far as it ever opened and the water was boiling then. Our altitude is 3800ft.
Cummins in Worland says they will have us two thermostats tomorrow. I will boil them and see, but I know an eighth is not enough opening.
Thermostat Replaced!
I had noticed over the past two towing outings with our 8800 lb 5er that the temps were climbing up about 6-8 degrees hotter than usual.
Not overheating, but running hotter than usual.
Decided to get a new thermostat. Got the part under warranty, and put it in myself.
The old one musta been pooched for sure, cuz she runs nice and cool now.
Both the old and new thermostat were stamped 180 deg, but both had different part numbers.
I also know that there was a TSB out for this, and I fell into the serial number range, so I figure this was one of the original thermostats in the bad batch.
Glad to have the "new" one in.
Shawn
I had noticed over the past two towing outings with our 8800 lb 5er that the temps were climbing up about 6-8 degrees hotter than usual.
Not overheating, but running hotter than usual.
Decided to get a new thermostat. Got the part under warranty, and put it in myself.
The old one musta been pooched for sure, cuz she runs nice and cool now.
Both the old and new thermostat were stamped 180 deg, but both had different part numbers.
I also know that there was a TSB out for this, and I fell into the serial number range, so I figure this was one of the original thermostats in the bad batch.
Glad to have the "new" one in.
Shawn
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Issue 128 – Digital Version
Digital Magazines
FREE!
TDR Test Drive - Digital Edition
Renew
Subscribe
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Back Issues
Subscription Status
Address Change Form
Buyer's Guides
Ram Diagnostic Trouble Codes
The Perfect Collection
The Perfect Collection Vol. II
TSB Updates
Dodge/Cummins Historical Overview
Cameron Collection
What Makes Us Tick?
Product Showcase
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