i do not have the 3000gsk yet for my first gen. so seems as though my max rpms are at 2500. since thats not really maxing out teh motor is it ok to just hold it to teh floor while pulling grades?

Im an ex gasser and never floored while towing before.

so im curious as long as temps stay normal and arent climbing is it ok to just stab it and let it pull and drop gears as needed?

thanks. jiMMy

 

Cummins says put it on the floor and let it wail. Just keep an eye on the temps and egt's.

 

Yep, RPM is your friend. Just keep it wound up and let it do its thing, the automatic won't let it lug. Even once you get the 3200 RPM spring you can do the same thing, won't hurt the motor with RPM. It's lugging that kills 'em.

 

This one is a little off topic, but since we are talking about lugging - Why is it so bad to lug a diesel? I have always heard this, but nobody knows why, so... why?

 

Real diesels produce enormous torque and heat at lower rpms. You can get very high exhaust and head temps at lower rpms. This can damage the head and even cause piston failure. They produce less heat at higher rpms. I was very frustrated because I was not developing full rpm's It turned out that the linkage kept me far from true WOT. I would sometimes hit a hill a little too slow, egt would rise rapidly, I would downshift and lose headway. After correcting the linkage problem, I could downshift without losing a lot of speed and things would cool down.

 

It's bad to lug any engine because the oil film between the rod bearings and the crank is easily displaced at low rpm. This leads to a rod knock eventually. Lugging is particularly bad for a diesel because the piston spends more time at high temp and pressure when lugging. A diesel that is lugged regularly will end up with cracked pistons.

 

you have not done much pulling with a 24 valve. They have much more heat at sustained high rpm than low rpm. This is both EGT's and coolant temp.

 

Sounds like you may need a larger turbine housing to bring down the EGTs.

 

While this is also my opinion, it stands that anything near stock in a 24 valve gets hotter as the rpms rise above 2600 and are held constant.

 

A different cam would help that. Longer lift and duration to help airflow What is your boost level at in those conditions?

 

In all due respect I think you missed the point. I don't have a problem, my engine performs great. I use it to pull freight not race. I was just commenting on the fact that contrary to what was posted, the 24 valve gains heat and EGT's when sustained pulling above 2600 or even 2500 at wot. Mine does not rise above acceptable limits, but there is a difference.

 

You're right, I did. At least in respect to thinking yours getting getting hot. But it would help the top end on any of them that do.

 

so back to my issue, just floor it and go i guess? jiMMy

 

Sorry to steal your thread, Jimmy. Yes, just let her rip. Especially since you have gauges.

 

The gauges will tell you what you need to do. Don't let the EGT's get too hot, run wherever the boost pressure is the highest, and don't fry your tranny. As long as you do all of that you'll find out where your RPM's need to be for a certain load/grade.

Also, a modified tranny might give you a bit more pulling torque. Sometimes those torque converters just allow the solid diesel torque to just spin into oblivion, eventually frying your tranny.