Max MPG with a F250 7.3IDI Single Cab with a E40 Trans? - Diesel Forum

jlrsn · 12-19-2005, 10:35 PM

I have a chance of buying another 89 F250 at a right price but this one has a E4OD Transmission. What type of miles per gallon can I expect to get when driving on a flat (minimum hills) freeway if I keep my speed at 60 MPH max and what would the engine RPM be?

What would a Gear Vendor OD do with MPG?

What MPG equipped as above pulling a 6,000 lb trailer at 55MPH?

Thanks,
Jim Larsen

cdnsarguy · 12-19-2005, 10:50 PM

If it has 355 axle then .........

355LS axle.....235/85/R16 tires........in OD

60mph....1650 rpm
70mph....1800 rpm
80mph....2100 rpm

I can average about 18-20 if I drive 60mph.

jlrsn · 12-19-2005, 10:59 PM

Thanks a lot,
That was what I wanted to know. What should I expect if it has a 4.10 rear end. I also forgot to mention that this truck is 2WD.
Jim

AMMODYTE · 12-20-2005, 11:14 AM

I don't have a tach (van) for my IDI, but the E4OD transmission slips in overdrive (at least that's what the trouble code says, I don't feel a thing), so my right foot is VERY gentle on the pedal. I should also say that the truck weighs 8500 pounds with a full tank of diesel, but without the driver. The Dana 60's (4wd) are 4:10, and my tires are 285/75R16D (BFG AT T/A).

Having said all that, I can now say that my fuel efficiency is a dissapointing 10 MPG. The motor is a practically brand-new Jasper. When it had the old motor, blowby and all, I got 15 MPG. This was on 245/75R16's though. Perhaps as the motor wears in, efficiency will improve?

You asked "what can I expect" and I thought a worst-case scenario would be appropriate among the otherwise rosy picture you will see, as our users brag about the great mileage THEIR truck gets!

Barebackcwby2003 · 12-20-2005, 12:31 PM

lol ammodyte. I have to agree with you there, cause I am "one of the guys who brags about my mileage." (around 16-20 depending)
I do have a friend with a pretty well cobbed up 88 250-350 what ever u want to call it, (read my signature) Although it is 5-speed 4x4, and with the banks kit he can get around 14-16 MPG with 4.10's. Towing 5500 or so, it is around 12.
The worst I have ever gotten was an empty 24ft. BP trailer at about 3K Lbs. (with those nasty, horrible, 4 or 5 foot tall mesh gates in the rear!) was 14-15 MPG (I drive the 92 in my signature)

as far as a gear vendors, If I was to add one on my truck, id probably get around 20 or better with mixed driving, I couldnt possible imagine highway miles! 25 maybe just turnin 55 60? but forget pullin hills! even a little ant hill! and forget towing. a gear vendors is better suited for a truck with 4.10's.

For what your lookin at, gather your own opinion after driving. my truck isnt a nutless wonder by anymeans, but with my 3.55's smaller hills kill me if im turnin anything under 1800 RPM's at the bottom of a hill, i'll be lucky to be doin 55 at the top, W/O any smoke on the way up!

i guess finally, i would say anywhere between 10-16 MPG, it all depends upon the engine, your right foot, conditions, and anything done to the truck to help it breath and eat fuel. Hope this helps!

Gibson · 12-20-2005, 12:33 PM

a freind has a '92 super cab 3/4 ton 2wd with a ZF-5 and 3:55 rear end he gets 16-17mpg at 70 mph (2050rpms) stock tire size. my rig gets 14-15 at 65-70 turning 2400-2600 rpms with stock tire size.

Barebackcwby2003 · 12-20-2005, 12:36 PM

Oh I also wanted to mention, a previous work truck I used to drive, 1990 F-superduty, single cab, 2 wheel drive, 4.88 gears (im assuming as I have heard this is only gear possible for them [img]/ubbthreads/images/graemlins/shrug.gif[/img] someone correct me if im wrong) RELIGOUSLY loaded around 9-11K combined weight with no mods just bone stock and chocking exhaust only got around 10 MPG with the E4OD!

diamondtguy · 12-20-2005, 02:33 PM

I get around 15mpg bombing around in the city (OD off) and can get just over 20 on the highway.I have 3.55 gears.Having the camper on kills the highway mileage.(mid 80s Okanogan 8ft)(read heavy)
Note....these are Canadian gallons..

Cory

DSBlack · 12-20-2005, 03:37 PM

I get 14 empty. and a bit 10 with the TT. But I can't drive 55-60. I am always trying to run 65-70.

rawpower · 12-20-2005, 04:14 PM

i get 10 empty

jlrsn · 12-21-2005, 01:54 PM

I want to thank everyone for your input! I'm amazed at some of the mileages per gallon, or lack of, depending on gearing and driving styles. With my 89 F250 with my ZF5, 4.10 Rear, and 285/75R16 tires I get 18+ MPG on the highway if I keep my speed down to 60MPH and 14 MPG if I'm towing my 6,000lb TT at 55 MPH (Calif Speed Limit for towing).

aford4ever · 12-21-2005, 09:34 PM

Hi Jim
I'm new here but I'm driving what your looking at: 89 Lariat f250 7.3idi with a automatic tranny...2wd. Single cab,
Most my driving is 55mph I get a steady15.3-15.4...no topper and tailgait is up.
Randall

jminix · 12-23-2005, 11:33 AM

I currently get 20 empty at 55mph, 16 at 65mph and 13 at 75mph. Truck details are in my sig.

I'm thinking about switching my gear raito and/or tire size. Perhaps 3.55's or 3.73's. Any opinions? I'd really like to be able to get 20+ mpg at 65mph, but don't want trouble going up moderate hills with a medium trailer (~3k lbs, 20' enclose motorcycle trailer).

hweaver · 12-24-2005, 02:14 PM

I think my 90 F-350 4X4 Crew Cab has 4.10 gears. It will get 16 mpg on the highway without the cabover camper.

hweaver