I searched on thermostat on here, and came up with the old thermostat 3928499, and then that a new tstat came out that is supposed to 'fix' the cycling' problem that the older one had. I saw infidel post up a bulletin that it's normal, some saying that the new tstat is the way to go, and others saying it's a piece of crap and that it's in a landfill.

I have an Auto Zone tstat, and some on here have said that could be part of the problem for my heat not working and my temps not coming up. I figure I might as well get a good tstat back in there before I go sticking cardboard in my radiator.

Thanks!
Dave

 

When I bought my truck, the P/O put in the "updated" thermostat. Took forever to warm up in the winter. I went with the old version that cycles, and I'll never go back.

 

I got the Cummins p/n at work I'll pm it to you tomorrow along with the seal #'s. The seal #'s however will be Stant instead of Cummins, FWIW use he Cummins stat it's the most recent updated and best one to use for quality, far superior to most others.

 

Go with the old style stat.
I think the only reason the new one was introduced is because people were complaining about the normal, doesn't hurt anything at all cycling of the gauge.
The "improved" stat runs too cold.

 

When i got mine at cummins this spring, the fellow said that there was only one tstat available.

 

Jeez nobody in town has this thing. Guess I have to 'special order'.

Thanks for the info!

 

Greetings,
I'm sorta' new to the CTD program, and not nearly as knowledgeable as the folks here, hence the reason I joined. I have a 95 & 96 (ones gotta' go) 2500 xcab 4x4. Mainly I'm driving the 95. The first frost was a coupla' days ago. I was reading in the owners manual the importance of 'operating temperature range', my ctd takes forever to get there if at all when outside temp is 50 or less (we've only had 1 day of it so far), I can only imagine what it may be like when December rolls around & we stay below freezing for weeks on end. My first DTR question is how do you correctly rectify the UNDERheating problem, with a correct thermostat or grill blankets???

 

Mine is from an old chrysler gasser, it runs a bit hotter (195*F) than pretty much any other thermostat I can find and doesn't do any of the cycling. The first time it opens it hits the high end of the normal operating temperature then settles right down to the middle. I feel some heat after a mile or less but normally not full heat for at least 4-5 miles.

Grill blankets help it heat up a little faster only if your thermostat is doing it's job properly. Mine wasn't getting above 160*F before, now always stays at 190*F or higher.

 

One thing that is commonly overlooked is the radiator cap, if it can't build pressure like it should it'll trend to warm up slowly, have the cap tested or just replace it.

 

What is meant by the term 'cycling' regarding the thermostat & cooling referred to in this thread??? I'll check the cap tomorrow, thanx for the thought!!!

 

Cycling is referring to the t/stat opening and closing repeatedly more than it should, but a dying or half dead or just plain dead cap don't help. If the cap tests at less than 15 lbs get a new one, new cap is rated for 16 lbs. The boxed Stant is #10230 for just a plain ol' cap.

 

Cycling is a normal occurrence on CTD's? I don't recall that being a problem on gassers.

The boxed Stant is #10230 for just a plain ol' cap.

This is a 16# cap?

 

Yes it is 16 lb, I think the blister pack # is 11230, same same different package.

 

From Cummins:
THE COOLING SYSTEM USED ON THE CUMMINS DIESEL ENGINE EQUIPPED VEHICLES PROVIDES THE CAPACITY AND PROTECTION OF THE HIGHER GVWR AND GCWR RATINGS AVAILABLE ON THESE VEHICLES. OWNERS SHOULD BE ADVISED OF THE NORMAL SLOWER WARM UP AND LOWER ENGINE OPERATING TEMPERATURES ASSOCIATED WITH DIESEL ENGINES.

THE COOLANT TEMPERATURE GAUGE WILL FLUCTUATE ON DIESEL ENGINE EQUIPPED VEHICLES. IT IS INFLUENCED BY VEHICLE LOAD, OUTSIDE AMBIENT TEMPERATURE AND EXTENDED IDLE TIME. THIS FUNCTION IS CONSIDERED NORMAL

GAUGE FLUCTUATION WILL BE NOTICED MOST OFTEN UNDER STEADY STATE (HIGHWAY) DRIVING USING THERMOSTAT (P/N 4796869). PLEASE ENSURE THAT YOUR CUSTOMER IS AWARE OF THIS NOTE PRIOR TO RELEASING THE VEHICLE.

 

Place here in town wants $29 + 8.25% + $10 freight to get the thing! ($41.40)

Anybody have a good online source for Cummins parts? I don't mind paying $29 + tx...but $10 freight on a little thermostat...they can keep the thing! I'm sure it would fit in a USPS $3.80 or whatever envelope. First time I've ever heard of someone charging freight. You'd think it could just be added into whatever orders/stock are already coming in.