I Just test rode a Chevy and a Dodge Diesel. Wondering why the Dodge has such a lower redline?
Chevy was at 4800 and dodge was at 3200.
I like different items better on either truck...but love that mega cab...
still cant make my mind up...I can get employee pricing on both...but a 2007 (classic chevy) is about 6k less
and has less plastic...

 

not sure why but i would imagine the dodge being an inline 6 which makes power out of lower RPM's vrs. a v8 which i think the duramax is. just my thoughts

 

Since horsepower is a function of both torque and RPM, maybe GM gives their diesel a broader RPM range to get a higher hp rating?

 

I was really surprized that the Duramax had such a high redline...my 3 cylinder in line tractor redlines about 3k also.

 

unless you're racing... rpm's aren't a problem with a diesel. you didn't ask but, GO CUMMINS.... are you crazy ! :-)

really... a friend just bought a Dodomax 3500. It's has 5K on it and he's already lost a injector and/or piston. It's a work truck that's completely stock. He's been hauling loads of cut down trees with it which has been the only load he's put on it. He said it's ran hot since new which is the same thing I've heard from other do do owners. It is under warranty but, why should that happen this early in the truks life ?

Anyway.... BUY A CUMMINS :-)

 

I need to find that pic that shows the size difference of the pistons between the power joke, duramax and cummins where the cummins piston and rod just dwarfs the other two.

RPM is dependent on many things, rotating mass for one, second is your stroke. the DM and PS both have shorter strokes and lower compression ratio's then the cummins, thus you can winde those engines up much higher. when the 24 valve engine was introduced back in '98 the redline went from 2800 to 3200 simply due to piston redesign and use of lighter alloys.

I know the DM will engine brake up to 4600RPM. . .I think I would change my drawers after that

 

Engine RPM limiting is a function a several things, on gassers it is typically a function of mechanical engine limits (of valvetrain or other rotating equipment), however diesels is a factor of combustion speed, at higher RPMs the fuel cannot combust quickly enough to provide power or prevent burning fuel from going out the exhaust. The difference in redlines may be a factor of design, Cummins designs the engine to provide the desired power and have a LONG life, whereas the Duromax (Dodomax as triton lovingly refers to it as) is probably designed to make the power output desired by increasing that redline. This can be done several ways: design in hot spots, if you ever looked at turbocharged gassers hot spots are BAD, because they cause preignition and on a diesel it is the same thing, but the timing can be controlled and make the power created come out at TDC instead of BTDC... There are several other way, and I am not claiming they did this one way or another, however the point is that Duromax made the power by increasing the redline, and what seems to be a common thread in lack of reliability (my friendsDuromax had all the injectors crap out after only 80k...). Go with the Cummins you will be MUCH happier! (And that isn't JUST my opinion... many others will tell you that... even guys who had Duromaxes and Powerstrokes...)

 

I think what everyone is trying to say ...... "Duramax needs the extra RPMs to make up for the crappy motor".

 

The crappiest motor I tested was a 2006 26k POS ford king ranch (right before the chevy and then the dodge) the turbo lag was bad...and just had no power...and I was flooring it...

I do like the CTD best...and the same HP at a lower RPM should be the goal of any engine.
And the Mega Cab will be the clincher..its either a Mega cab or back to another suburban

 

The crappiest motor I tested was a 2006 26k POS ford king ranch (right before the chevy and then the dodge) the turbo lag was bad...and just had no power...and I was flooring it...

I do like the CTD best...and the same HP at a lower RPM should be the goal of any engine.
And the Mega Cab will be the clincher..its either a Mega cab or back to another suburban