I just recently got my first truck, a 78 F150 Supercab 4x4, with the 351M. The body is rusting away, but the frame and axles look great. It had a gas leak when I got it but I rebuilt the carb and it runs great now. This isn't my first car but it is my first carburated one. But anyways, now on to my questions.

What size tires will fit on the stock wheels, and in the wheel wells, on this? I have some 32x11.5x15's off my Jeep that look like they'd fit it perfectly. The old tires are about to fall apart.

I have an old friend with a 78 Bronco. He said the front is geared a little higher (numerically) to help it climb better offroad, is there any truth to this? When the truck is locked in to 4lo it doesn't like to move much. Definitely doesn't like to turn at all, less than my Jeep does when it's in 4lo. Then it's close to impossible to get it out of 4lo at the t-case, or unlock the hubs. Why is it binding so bad?

Very stupid, but I can't seem to find a straight answer, how much and what weight oil does it use?

Lastly I'm looking for some easy things to do to it, for performance or looks. I keep hearing these engines are smogged to death, is there anything I can do to help that without starting to buy a new intake and carb?

There's another one I have but I can't remember it right now, so I'll post it when I do. Thank you guys for the help, I'm glad to be a part of the forum now.

 

Bump, any help here would be appreciated. Specially on the tires.

 

Have you tried backing up 10ft or so to "unwind" the drivetrain? I always thought the gear ratios were supposed to be identical, as well as tire size front and back

 

the tire's you have should fit just fine might hit the frame just a bit in a hard turn but nothing serious. The gear ratio in some of these truck's was like 4.09 and 4.10 front and rear respectively had nothing to do with them climbing better or worse they just drove better,and as far as them coming out of 4l hard all mine do the same dam thing.Does the engine have good compression and in general good shape? if so then intake,headers,and exhaust will help a lot,but you can gold plate turd and it will still be a turd!

 

Thanks, I'll try and get them on today then. I've backed up, gone forward, park, neutral, tried everything. It just seems like it unlocks whenever it feels like it. And that is what he was saying, he just thought it was supposed to help I guess.

I haven't checked compression, but it runs great. Enough so that I'm wondering if it's been rebuilt before. Engine mods are a ways off, but I'm sure I'll end up doing them. I don't need a speed demon, just want it to have enough power to get out of its own way and tow.

 

Usually If I put mine in neutral it pops right out but not always

 

Well i have just got my first truck as well, 78 F150 4x4 reg cab with the 351m as well, I got it thinking that it was a stock 351m, turns out when i got home and inspected the motor, it had a edelbrock performer 400 under it covered in grease and dirt, a set of headers, and a holley 4bbl carb.

Any who, our 351m's yes were smogged to death. What we need to wake up our motors are a good Straight up timing chainset, because stock from the factory they retarded our trucks (ive heard) between 4* and 10*. They straight up (which means straight up at 0*+) which will open up and let our motors breath alot better. I will soon be doing a complete rebuild on my motor, putting in a Comp Cams Extreme Energy cam and a straight up timing chainset, and a 400 crank to stroke it to a 400.