I have a 89 F250hd with 460, 4.10 rear, C6 and factory towing package. I am real pleased with it. However, it gets real poor mileage, of course. About 9 in mixed driving and 11 on highway only, while it is a great towing machine not that practical for daily commute or the grocery store.

I am wondering if in the future I could find another truck. First, keep in mind I don't tow very much and would want something for a daily driver also. But, I don't want to give up big block.

So, I am considering, for example:

1) Early 90's F250hd, with 460 and overdrive tranny. I think they only came with 4.10 rear. (unless 3.55 was special-ordered).

2) Early 90's Chevy 2500hd with 454 engine and 3.73 rear and 4L80 heavy duty tranny.

I tow a trailer which weights about 6500 lbs dry and probably 8500 full. A few thousands miles per year at most and likely much less than that. I know with 4.10 my towing capacity is up, but that, in conjuction with no overdrive, gives abysmal mileage.

I don't have a real brand preference, I had real good luck with this F250 and also real good luck with a chevy sedan with V8.

Question - how much mileage improment can I get with choice (2)? Can I get up to 14 mpg on highway only, turning say only 2200 rpms instead of 3,000 like now?

 

After some thinking, I see it is doubtful I will find a truck as nice as this one. Therefore I decided to install Gear Vendors overdrive, since that's the only problem with the truck.

Nevertheless, would still be interesting to see responses to this thread, from those who have some experience with Chevy 2500HD and 454.

 

I've delt with both of the trucks your looking at.

The Ford is more powerful, but I believe the GM is more comfortable and it is more fuel efficient.

1991 was the first year of a OD Automatic in an HD GM truck, as '89 was the first year for Ford.

From a mileage standpoint, I would believe the Ford would avg. around 13-14 mpg unloaded and the GM would avg. around 14-15mpg unloaded.

 

The above of course assumes GV overdrive.
I haven't heard of any 460 which got that kind of mileage, unless of course it had an OD. 454 is equally bad, from what I hear (but no personal experience with one)

3 speed is really not good. Reliable, but I don't like it.

 

It really depends on your definition of good.

In their times, they were the best transmissions available. Of course then, gas prices weren't 1.65 gallon either.

 

OD - usually 4th speed in autos was added to reduce RPMs and lower fuel consumption.

Most new trannies with OD are not reliable. It is safe to say that modern trannies are almost as good as old 3-speed trannies. Chrysler 3-speed Torqueflytes (sp), and Ford's C6 and others are very good trannies. I never had problems with them and don't hear others complain either.

Well, I also had good luck with Chevy's 4L60 transmission. 3 speed + 4th OD. Which explains how a 4500lbs station wagon with a V8 can get 22 mpg on highway. I find this very impressive.

C6 and other trannies like it are obsolete, antique design from the 60's and aren't popular in our times. Who would buy a new truck with one.

I cannot wait until I get the funds to install Gear Vendors OD on this truck. It will be the first and last modification I make to the vehicle. I thought about getting a newer F350 (for me, that means 1992-1993 at best) but it is doubtful they are any better than 89 I have and certainly not cost efective.

 

I would recommend a F-250 over the chevy 2500. First reason being past experience with both brands. We have a 1990 F-250 460 and E4OD transmission and 3.55 rearend. This truck does not get the best mileage when driving town 10-12mpg, but it does get around 15 on the highway. We have even got 17 out of it before. Another reason i would choose a F-250hd over a chevy 2500 is because of the different variations of a 2500. Some are on 6 hole wheels and have a semi floating axle. Then there are two different axles that have eight bolt hubs. The only way to be sure if a chevy 2500 is a HD is to pull of the rear hubcap and look for a full floating axle. It is much easier to tell the difference between a F250LD and a F-250HD.