Engine/Transmission (1998.5 - 2002) run's hot while towing up a grade

[MSalvatore]

So I was towing about10k up a 9% 3 mile long grade. engine temp was 240 at the top and egt's were at 1400. the comp in sig has no pump wire attached. what can I do to lower engine temp and egt's while towing. trans is new dealer replacement and trans temp never passed 180 while towing. Do I need a bigger turbo?

 

[NoSeeUm]

Sounds almost like you need to slow down and drop a gear?



Jim

 

[MSalvatore]

od off and 40 mph. I was struggling to maintain that without going to the floor.

 

[Devan Manis]

Have you moved your crank case breather? i would move that from out behind the fan, take out the radiator and pressure wash the crap out of it, and the condenser and intercooler. that should at least help with the engine temp's.

 

[59Turbo]

Either remove and clean the radiator or replace it, it's probably clogged and the air isn't flowing through it. Also replace the t-stat with the updated one from DCX.

 

[CHornsby]

Not sure how many miles you have on yours, but I just changed my Tstat and saw that it was all jacked up ... ... ... ... with just over 100kmiles on it. Put in a new 180 Tstat and it runs nice and solid now. Haven't towed with it yet, but then again I don't have much to tow except a 6X12 enclosed trailer. I still noticed a difference. Just as a precaution, I added Water Wetter to the coolant system after I changed the fluid out as well. Only think I haven't done was pressure wash the radiator, but I believe the Tstat was my main problem.

 

[keimmmo]

Be careful pressure washing radiators. The pressure can bend the cooling fins and shut off the air worse that a dirty radiator! I wash mine with a combination of dish washing detergent, garden hose, and compressed air to blow out the crud the soap and water has loosened.



I have to pull the radiator on both my trucks every couple of years and wash out the bugs and crud. It makes a big difference in operating temps!



The 180 thermostat in the 01. 5 made quite a difference when towing. The 92 still has the original thermostat in it with over 330k miles on it!



It also helps to slow down and keep the engine rpms up by downshifting. Reving the motor moves more air through it... cooling the motor better.



Steve Keim

 

[PC12Driver]

How cool would you expect a truck making ~350hp to run while pulling 10,000 lbs up a 9% grade for 3 miles? A stock truck would get warm doing that.



What were your RPM's and boost #s?

 

[MSalvatore]

boost was 30psi and rpm's were about 2800-3000 I think

 

[wcjp]

How fast were you pulling the hill? What was the ambient temp? Did the fan clutch engage? Also, I agree with the others. The combination of more power and a dirty radiator will do it. The radiator may appear ok. It the oily mist that attracts dirt that causes the problem. When removed try simple green and low pressure garden hose.

 

[PC12Driver]

boost was 30psi and rpm's were about 2800-3000 I think

That's quite a load on your engine. And you're holding that on a 9% grade for 3 miles at 40mph, which would be like 4-5 minutes or so. I guess I don't see where the problem is... That engine is gonna get hot even if the radiator was spotless.



The only thing I would be concerned about is the 1400* egts. I'd let off a bit, since our pistons don't work so well in a liquid state. A bigger turbo could help with that in the upper rpm band, but the tradeoff is some bottom end performance. Even so, you'll still have high water temps when you work the engine that hard.

 

[Grizly]

1350 for 5 min = melt down don't it?

 

[PC12Driver]

1350 for 5 min = melt down don't it?

Rumor has it... Then factor in gauge error, pyro position, the averaging between the three cylinders that share the runner, and the actual temp inside the cylinder that will read lower at the pyro because of the additional timing advance from the UFM...



My personal limit while towing is 1200*, which is 50* less than the Cummins-suggested 1250* max continuous.

 

[MSalvatore]

I did not drive for 3 miles at 1400* and engine at 240* it was at 1200-1250 for most of it only last 1/4 mile or so it climbed to 1400. I will clean rad/condenser etc... tomorrow how do others tow alot of weight with no heat issues? twin's?



Marc

 

[BarryG]

Earlier this summer I noticed my temps had started getting hotter while going up grades towing or not. Not really hot but 20-30 degress warmer than they used too. Pulled the rad and washed the outside. Couldnt believe how much crap came out. I expected it to be dirty but not near as dirty as it turned out. That is with a screen and having relocated the breather bottle 150k ago. I also replaced my t stat at the same time. Temps dropped noticeably afterwards, back down to where they used to be.

 

[NoSeeUm]

That's quite a load on your engine. And you're holding that on a 9% grade for 3 miles at 40mph, which would be like 4-5 minutes or so. I guess I don't see where the problem is... That engine is gonna get hot even if the radiator was spotless.



The only thing I would be concerned about is the 1400* egts. I'd let off a bit, since our pistons don't work so well in a liquid state. A bigger turbo could help with that in the upper rpm band, but the tradeoff is some bottom end performance. Even so, you'll still have high water temps when you work the engine that hard.

If it were me I would take this advice. To me, it sounds really like you have 3 issues going on.



Hot engine coolant temperature

You are likely running more Hp than the stock cooling system can reject, but it still seems a little hot for the speed you were going. Cleaning the radiator externally, an engine coolant flush and or fluid level / quality. I would also check the fan clutch to make sure it was working properly. If it is the fan clutch it would effect coolant temperature and EGT.



Hot EGT's

A larger turbo probably would help. So would a cam, a bigger intercooler or methanol injection. There is allot of knowledge here on TDR about what turbo(s) are good for towing. Contact a vender, and see what they think. Twins, will likely solve your EGT problems, but they are pretty spendy.



Transmission oil temperature

I am not expert with towing using an auto. But your low transmission oil temperature seems out of whack as in its too low. Pulling that grade your temperature should have elevated. This could be because your engine Hp is way down. Or it could be where the temperature is measured. Again, I am no expert, but some temperature probe locations might not reflect true transmission hot oil temperature. Do you know where yours is mounted?



The only other thing I can think of is a possible exhaust pipe restriction. Are you running an exhaust brake?



Good Luck;

Jim

 

[Big A]

If you keep your EGTs down, your coolant temps will stay down. Clean your radiator, and relocate your crankcase breather.

Big A

 

[CFAR]

You are slightly bombed which will raise your water temps. Big A is correct, if you are running a hy35 at 30 psi, that might be pumping hot air into the engine and in front of the radiator.



I have the same problem, gotta watch the egts.

 

[NoSeeUm]

You are slightly bombed which will raise your water temps. Big A is correct, if you are running a hy35 at 30 psi, that might be pumping hot air into the engine and in front of the radiator.



I have the same problem, gotta watch the egts.

Marc's sig says he is running an HX35 and DD2's which are about +75 Hp.



Jim

 

[MSalvatore]

Update. I pulled the radiator and it was filthy. so I flushed it out . cleaned it and intercooler and condensor. put it all back together and went for a ride It was about a 1/2 hour ride. engine got to 19 and stayed there, I shut it off and checked the clutch fan and it spun with little resistance. at 190 shouldn't it be locked together?