I am considering replacing the stock 240 with a rebuilt 300. I drive from Florida to Maine hauling produce both ways I have made 4 round trips with the 240 but blew a ring this fall. The vin plate shows N for tranny code and 29 for axle which I looked up finding the rear end gear ratio to be 5.87 which i may want to change also. the 240 was screaming at 60 so most the east coast trip I keep her at 50. I would appreciate any advice.

 

If I was running that far commercially it would more economical to find a newer model truck.

 

Cant give you technical help but my personal advice is I had my 240 rebuilt to a 300. Still have the 4 speed manual tranny and kept the
1 barrel carb. It runs great, has good pick up. Not sure what mileage is now but the gas gauge needle moves VERY slow.

 

Jim, Welcome to FTE & the Slicks Forum.

3000 + round trip in a near 50 year old truck is something we don't see here every day. Gas mileage has to be out of sight. Give us more detail about the truck that you are using.

I am guessing that you are using a 6 wheel F350 because of the rear ratio. That old truck was designed for a top speed of 45-50 mph.

The 300 is a larger version of the 240, so the swap should go easy enough. The I-95 run is pretty flat for the most part, not mountainous like the left coast. Getting a lower rear ratio is gonna help with the mpgs.



John

 

Yes, John The gas mileage is bad 8 or 9 miles to the gallon and with the stock 16 gallon tank my range is short filling up every 100 miles or so the 1900 mile trip takes 19 fill up and $800. the cost of the trip doesn't bother as much as the wear on the old truck as I brought back 2000 lbs of winter squash,500 lbs of apples and 100 lbs of garlic that I grew in Maine which brought almost $3000 in cash to cover the trip. I love the old truck and want to continue to make this migration with her.
The truck came from Bates city Missouri 13 years ago it is a six wheeled truck which had the suicide 16 inch split rims which I replaced with some custom tubeless rims from Stockton wheels. The f350 has a Ranchers bed with flip up stake sides and dump body and a 20 ton pto drven hoist.

 

Jim, 2600 lbs can be hauled on a 100/150 although I am not suggesting you do that for that long road trip.

I would suggest that you look at a much newer 3/4 ton, maybe with diesel and OD tranny. Some guys are using Cummings is it B(4) swapped in. Take the bed off and build a custom flat bed. You might get up in the 15-18mpg range with OD.

Keep the old truck for local use short trips. Yours has a Dana 70 so finding lower gear ratios is going to be harder.

I think you are using too much truck for the trip and load. You might find a newer chassis and fab your sheet metal to it. You have options.

Go ahead with the 300 replacement to keep that truck running, get the new replacement up for next spring runs.

You might even go with a box truck and haul 12,000lbs of your good produce and put some real bucks in your jeans.


John

 

While I would agree with most of these other guys on this is a trip for a newer truck, I also have to say I completely respect the capability of your truck to go the distance, and for you to make the trip in what is not a truck with a smooth ride.

That being said, I have a 66 F100 with a 240, and as soon as this gives up the ghost, I will replace it with a 300. I also am trying to figure out any minor mods that might give me a couple miles to the gallon. If you want to drive the old truck and the money and the ride don't cause you any pause, I say get the 300 and keep on trucking.

 

I use Ole Red on both end of my migration, hauling mulch, manure and hay. That open dump bed is great. and can't afford the the cost and details of owning two vehicles. I am sticking with Ole Red and just want to make the trip easier on her.
Why is the Dana 70 difficult to change gears in?

 

Jim, I'm sure that you are grown and luv your ol girl, but depending on a 50 year old truck to make east coast runs with produce isn't the wisest move that you could make. Being stuck on the side of the road for 3 days to a week with rotting produce because parts can't be found is risky.

You start the search and come back in a week and post that you have 3.50-3.75 ratio gears for your Dana 70.



John

 

The engine swap should be a bolt in affair, the rear axle a slightly different animal. I would search CL and see if you can find a local F350 for sale, and buy a newer complete rear axle with 4.10's, the 300 will love that combo.
I am glad you keep using your truck for what it was designed for!! KCCO
DON'T buy a new one, upgrade the old!

 

Hmmm? Sorry if this is a bit off-thread.

My '61 F-350 has its original Dana 70 with a 5.13 ratio. The lowest ratio offered in '61 by Ford for the F-350 (with Dana 70) appears to have been 4.88. Given my desire to keep my truck largely original, and keep my Dana 70, the difference between 4.88 and 5.13 ratios is not sufficiently dramatic for me to pursue the option of swapping gears. Were Dana 70 axles available -- possibly in different years or for different makes/models -- with considerably lower ratios? (Yes, I know, my ignorance is showing?)

Thanks,

Steve

 

if u need tech help, you ought to drop down to the inline six forum. if u change to a 300, you ought to check your crank to see if it is forged. People search for those and they are rare.

My 300 is punched up, but I don't notice difference between it and the stock 390 I replaced.

 

I am planning on using the 240 for the core on the professionally rebuilt 300

 

I am confused about the carrier break on different dana 70s found this? Thick Gears vs. Thin Gears and Axle Carrier Breaks Explained

 

Steve, No they were not. Keep in mind your truck was designed for a top speed of 50 mph. There are not a lot of options for those gears.

Remember your truck parts are ofver 50 years old. With enough money thrown at it, I'm sure a better ratio can be installed. But not for cheep.


John