Im new to the forum so sorry if this has already been adressed (if you could point me in the right direction or show me how i can search for stuff just inside of the 80-86 forum that would be great). I am going to buy an 86 f250 4x4 with a c6 and 5.0fi in the next few days and im curious on how easy it would be to convert it to a dually setup and if anyone has any experience and tips on it. Thank you for all your responses in advance.

 

If you are buying a f250 that originally had a 302 fuel injected engine, you are buying the light duty f250, not the f250hd. It will not have a full float rear axle in it. It also will have the dana 44 ttb hd axle up front.

If you want to convert to a dually, you can go aftermarket and get dually adapters. They simply bolt on and then you need to get the proper wheels and do something about the rear fenders. These adapters are not cheap though.

If you want to go factory, you will need to find a dually rearend and bolt it up. Be careful, you need a dually pickup rearend, there are also dually chassis/cab rearends which will not fit a pickup. You can get this from the pickup where you could get the dually bed also.

And then you need a complete new front axle. If you want to keep the ttb, you can bolt in a dana 50 ttb and then get the factory dually adapters and bolt them in. Or you can get a straight axle dana 60 and if it doesn't have the dually adapters, you can also swap them in like you would do on the dana 50 ttb.

For any truck previous to the 99 superduties, Ford never made a dually 4x4 pickup. They only made cab and chassis dually 4x4 trucks. So the parts you need for the frontend are coming from cab and chassis trucks, but the rearends from these type trucks will not fit a pickup.

 

 

Thank you! That makes this a lot easier.

 

The person im buying the truck from has a quite a graveyard of trucks going, I believe he has a same year dually but its 2wd. He also has a big old ford (20-40s ish) that has the dually set up in the front. And a scout II as well. Would any of these have some worth while parts I could negotiate?

There is also a 64 with the 9 foot stepside bed im considering. Im just unsure if that would fit the 86.

 

The old old truck will do you no good. The 2wd dually may give up the rear axle but be careful, it may have a oddball gear ratio and you need to get a frontend with the same ratio as the rear. Most f250 4x4's will have 4.10 axle ratios or 3.55 axle ratios. Stay with the 1980-1998 trucks to get your parts.

 

Im going there today or tommorow and I will see what other gems he has laying around and ill update you guys on the 2wd dually.

 

If it matters - to space out the downtime of the truck for the OP, could always keep with the singles on the front with the 44ttb.

Payload capacity and spare tire hassle aside.

 

A LD F250 is a poor candidate for a DRW setup as it used the F150 frame. Whatever you do, do not install dually adapters on the semi float axle or you risk the entire assembly coming out on the highway.

 

I always though that the frames were the same on the f150 and the f250 up until 1999. What is the difference between the frames in the older models? Does the LD trucks use the swish cheese frame?

 

Only 81 had the swiss cheese frame.
Not sure if there is a completely accurate consensus on the frame differences - maybe someone will chime in that knows. If not we need to start a thread to get people to answer a questionnaire with measurements and get that nailed down

 

I have personally looked at the frames. Dimensionally the f150 and f250/350 frames are the same, but the f250/350 frames look thicker. But I have not measured them so I cannot say how much thicker they are.

 

There is a chart on the frame thickness and c channel size. The LD250 is essentially a HD F150 with higher GVWR.

 

You wouldn't happen to know where that chart is, would you? Would be a handy thing to have when the topic comes up.

Out of curiosity I checked the thickness of the trucks in my shop building.
I placed the caliper on the bottom lip of the frame right in front of the parking brake cable bracket where it flattens out.

1985 F250 2wd (HD) : .23 in
1986 F250 Supercab 4wd (HD): .23 in
1980 F350 C&C 2wd: .26 in
1985 F350 C&C 2wd: .26 in

 

Ford = Flareside, a stepside is a Chevrolet.

1953/72 F350 Flaresides were available with a 9' Express bed, but not with DRW's.

Ford did not offer a pickup bed with DRW's until 1980 and then it was F350 Stylesides only.