Engine/Transmission (1998.5 - 2002) Mileage Max by Edge

[John - K5AWO]

Too big a hurry I think

well I took it up the mountain and it still pulls down to 45 mph. That's where the peek torque is in 5th gear which is around 1700 rpm's.

Um, I think you are expecting way too much from your truck at those low RPMs.

My truck is a stock automatic sort of; it has a triple disc torque converter. The axle is a 4. 11 which I am guessing is the same as you have.

My driving technique is a lot different that what you are telling us. The first time my truck down shifts from OD when I pulling a load, I lock the OD out and let the engine wind up in RPMs to what ever it takes to keep the MPH that I am doing. I never try to push it over 60 mph up a steep grade. I am quite content to keep the EGTs at or below 1100-1200 and whatever she does going up hill is just fine with me.

Whatever is at the end of the road will still be there when you and I get there. Quit being in so much of a hurry, and to hell with the traffic. If they get upset, that is their worry, not yours.

I am the one paying for my fuel bill, not the idiots out there driving a sub-sonic rice rocket m/c or a small car with a turbo on it.

I drive for fuel mileage and the speedometer can just run where ever it needs to run to let me get the max miles/dollar.

 

[DMillard]

John-K5AWO,

I have 3. 54's and a 6speed stick which puts my rpm's at 2100 at 55mph in 1-1 or 5th gear. In 4th gear the rpm's are 3100 at 55mph. At 16,000 lbs on a 6% grade in 5th the engine will hold around 45mph without having to downshift. 1700 rpms is where the peek torque of the stock engine is. At 19,500 lbs on a 6% grade I have to down shift to 4th gear because the extra weight pulls the engine below 1700rpms.

It's realy not a big issue and I like fuel mileage. I understand that with a timing tuner and a mild injector upgrade I can get more power and maintain the same mileage or even gain a mpg.

The Quadzilla MMM has made going through the gears a lot more enjoyable because the engine gains rpms much easier and quicker. Stock, the engine seemed to fight for higher rpms.

 

[DavidBates]

I have a Edge Milage Max in a 2004. More power & 7/10ths more mpg. Smarty Jr, is suppose to be the best for Dodge.

 

[blacksheepdiesel]

With a Smarty and RV 275's in my '01 6 spd with 3. 55's I could pull a 16,000 lb trailer up any grade in 5th gear and stay above 55 mph. That truck has over 800,000 miles on it now. The Smarty really helps keep the egt's low.

Godspeed,
Trent

 

[AABEN]

John-K5AWO,

I have 3. 54's and a 6speed stick which puts my rpm's at 2100 at 55mph in 1-1 or 5th gear. In 4th gear the rpm's are 3100 at 55mph. At 16,000 lbs on a 6% grade in 5th the engine will hold around 45mph without having to downshift. 1700 rpms is where the peek torque of the stock engine is. At 19,500 lbs on a 6% grade I have to down shift to 4th gear because the extra weight pulls the engine below 1700rpms.

It's realy not a big issue and I like fuel mileage. I understand that with a timing tuner and a mild injector upgrade I can get more power and maintain the same mileage or even gain a mpg.

The Quadzilla MMM has made going through the gears a lot more enjoyable because the engine gains rpms much easier and quicker. Stock, the engine seemed to fight for higher rpms.

A 3. 73 or a 4. 10 would had been a better gear. The 3. 54 is a high gear.

 

[DMillard]

I ordered them RV275's. $350 and no core charge. Can't wait to put them in. Might wait tell the temps get a little cooler though. It was only 109 deg today.

 

[Vaughn MacKenzie]

John-K5AWO,
I have 3. 54's and a 6speed stick which puts my rpm's at 2100 at 55mph in 1-1 or 5th gear. In 4th gear the rpm's are 3100 at 55mph. At 16,000 lbs on a 6% grade in 5th the engine will hold around 45mph without having to downshift. 1700 rpms is where the peek torque of the stock engine is. At 19,500 lbs on a 6% grade I have to down shift to 4th gear because the extra weight pulls the engine below 1700rpms.

I would say with that big of load you need to keep the RPM up and if the weight is pulling you down to 1700 RPM you are waiting too long to downshift. With that much weight and with such hot weather I would keep it above 1900 RPM. . . downshift at 1900 and let it wind up. That will be easier on the engine than churning away with your foot to the floor at 1700 RPM. . . the harder you work the engine the higher the RPM should be.

 

[DMillard]

I would say with that big of load you need to keep the RPM up and if the weight is pulling you down to 1700 RPM you are waiting too long to downshift. With that much weight and with such hot weather I would keep it above 1900 RPM. . . downshift at 1900 and let it wind up. That will be easier on the engine than churning away with your foot to the floor at 1700 RPM. . . the harder you work the engine the higher the RPM should be.

I'll keep that in mind, I'm still learning about the best way to run this thing. 1900 rpm would be about 50 mph and shifting to 4th would put me around the peek HP rpm. I just have to get used to the noise when the rpms are up there. I guess as long as the egt's and the oil pressure are good I shouldn't need to worry.

 

[Vaughn MacKenzie]

I remember back when the 24-valve engine came out Cummins saying go ahead and wind it up when loaded, it's designed for it. . . you could run it at 2700 RPM day in and day out and not hurt it. I've known of guys who drive fast down the highway with their 4. 10 gears turning mid-high 2000s RPM for long periods of time with no harm done

 

[bromano676]

you will like the rv 275's.



just keep an eye on the egt's.

 

[mhenon]

With a Smarty and RV 275's in my '01 6 spd with 3. 55's I could pull a 16,000 lb trailer up any grade in 5th gear and stay above 55 mph. That truck has over 800,000 miles on it now. The Smarty really helps keep the egt's low.



Godspeed,

Trent

blacksheepdiesel, do you have any idea what HP your running with the RV275's and the Smarty (Setting #2 or 3?)? That sounds like a nice step up for my '02.

Mike