Engine/Transmission (1994 - 1998) My 12V MPG

[rrl989]

Been driving my Ram since 12/97, really itching for a new 3500, but it's very frustrating hearing so many 6. 7's with 15'ish mpg. Drove my 3500 city/hwy for 1 week at 55 mph or less, minimum rpms in traffic, 368 miles, took 18. 231 gallons, that just over 20 mpg.



Hard to imagine mpg dropping with these newer CTD's over the years, too bad they don't offer a smaller, economical CTD for those that just occasionally haul.



Edited to 368 miles, not 268.

 

[KnightR]

Your fortunate. Been driving mine for two years now (98 3500. . 4X4) and imbar assed to say how many MPG's. Oh well always my one ton standby 454 Chevy dually, and with diesel out of sight in California looks like it will be my ride for awhile. Even gas motorhomes are getting popular again.

 

[Missouri Mule]

It the extra HP,weight and emission stuff on the newer trucks that cause the poorer fuel mileage.

To bad they don't offer different Hp and tq ratings like the med/heavy duty trucks.

When I bought my Freightliner the Cummins engine was standard I had the choice of hp ratings from 175/400 to 250/?. I settled for 215/520 but could of spent a few more dolllars and had a 215/605 engine ( which would get me up hills if I ever drove outside Florida).



Truck weighs about 11,000 empty, hauling small loads now a days mpg 11. 9 last year usually its 11. 5.

Mule came in a 19. 1 again last year (using to haul really small loads of produce. Wish this recession would end).

 

[surfbeetle]

Empty I get 24 mpg at 70 mph. Got 735 miles in my tank on a trip from Sacramento to San Diego once. So I agree, I don't like the prospect of lower mileage from the new trucks, but damn they are quieter and more comfortable.

 

[LVJUNIOR]

The only way I could get 24mpg is if my truck was the one on the trailer being towed

 

[champspa]

Mine gets 19. 9 on the road at 70 gets about 16+ around town. has gotten 23 mpg but only on a blue moon so who knows why.

 

[The patriot]

I went to maryland last week. There and back I got 14. 5.

Mine is stock with 370's. I lost about 1-1. 5 MPG's with the UTE bumper and I'm sure timing would help.

Oh and also, if I keep it under 2000RPM's it helps too. I drove too fast.

 

[GSchlegel]

Last fall my wife and I took a trip to Utah. Because it was late fall, put about 800 lbs. of sand bags in the bed along with the normal stuff. We spent a week there, she in classes and i would wonder around back roads, etc. Drove back harder than our normal 70. 2500 mile round trip. Averaged 23. 5 mpg. Long trips the old truck does pretty good for a dually. By the way, broke 300,000 miles about 2 weeks ago.

 

[ksoren24]

I have 257k on my truck and just got 22mpg on a 560 mile trip. Before the trip I had the timing set, valves adjusted and the kdp fixed and I used a fuel additive. I drove about 70mph the whole way and in my truck that is about 1875rpm.

 

[GAmes]

268 miles, took 18. 231 gallons, that just over 20 mpg.

Unless that was a typo on the miles you got 14. 7 mpg. So did you fat finger the calculator or the pc keyboard?:-laf

 

[The patriot]

I have 257k on my truck and just got 22mpg on a 560 mile trip. Before the trip I had the timing set, valves adjusted and the kdp fixed and I used a fuel additive. I drove about 70mph the whole way and in my truck that is about 1875rpm.

What size tires, or did you change the rear ratio?
Mine has 3. 55's and 265/75 tires. 2000 RPM's is more or less 70~ish MPH. Not by speedo, by GPS.

 

[JustDave]

For comparison, my 2500 averages 22 mpg, hand calculated and filled to the same spot on the filler neck. This is mostly highway driving on gently rolling terrain in southwest Georgia. My sweet spot is about 2000 rpm, about 67 mph. I'll notice a drop (21-21. 5) if I spend time in stop and go driving when I have to go to town. I've also noticed a drop in the winter but not sure if I let it idle more or there is a different fuel blend for (lower heat content?) for the colder winter months. The best I've seen was 23 mpg, non stop between fill ups, highway driving, at a constant 2000 rpm, no hyper miling.

My truck has 212,000 miles, stock wheels and tires, proper inflation and alignment, TST 11 plate with boost elbow, and no aero aids. Nothing over the top, just reliable and well maintained.



Dave

 

[rrl989]

Unless that was a typo on the miles you got 14. 7 mpg. So did you fat finger the calculator or the pc keyboard?:-laf

Thanks, meant 368 !

 

[SRath]

I have 257k on my truck and just got 22mpg on a 560 mile trip. Before the trip I had the timing set, valves adjusted and the kdp fixed and I used a fuel additive. I drove about 70mph the whole way and in my truck that is about 1875rpm.

What size tires are you running? I have 285/75R16's and my rpms are significantly higher than 1875 with 3. 55 gearing at 70 mph on the speedo, which I do realize is actually a bit faster than 70 mph actual.

 

[The patriot]

I guess he aint tellin.....

 

[Missouri Mule]

I have 265s and 3. 54 rear it is doing around 2000 rpm doing 70 on speedo.

 

[ksoren24]

Oh I'm tellin! The tires that I'm running right now are 235s, that is a size below stock. I just had them left over from my 90 ram and I needed tires so I put them on my 97. The rpm is a mystery to me too. I bought it a year ago and the transmission was just rebuilt, before I bought it, everything is stock, I had to replace the rear end so I know those gears were not messed with, it is a 3. 54. The guy told me that the transmission was rebuilt all stock with a triple disc billet convertor. The only thing that I can think of is that maybe the speedo was adjusted for the 265s that were on the truck when I got it? Does anyone know how I would check? Is it just a different gear that plugs into the transmission?

 

[GAmes]

Borrow a Tom-Tom or other GPS to find out what your real speed is. You can change it by replacing the gear on the speedo sensor. If the speedo is reading slow get a gear with fewer teeth. Be aware of the clock angle required when you reinstall the sensor.

 

[The patriot]

What GAmes said. If youre doing 1875 even with bigger than stock tires youre going to be well under 70MPH.

@ 70 with those tires I'd assume about 2200 rpm's more or less.

Your MPG calculations will be all off too. Those small tires will have you recording more miles than you actually covered.

Anyone with a truck that gets 20+ MPG @ 70 MPH has a true keeper assuming those numbers are accurate.



I got to look into getting mine timned up. I'm thinking 15. 5-16 deg BTDC. ???

2000-2200 rpm is my highway speed.

 

[Missouri Mule]

I had a customer put on the same type of tires as mine they were 235's but maybe narrower. They were as tall as my 265's.