Hi Everyone,

I just got a '93 F350 Dually with the 7.3 non-turbo and the 5 speed manual and am looking to get educated. Truck is in good shape, as far as I can tell it's all stock and been fairly well maintained. It's used mainly to haul a boat (about 7000 lbs), and also to get me to work about once a week. I've only had it a week now, but it's smoking a little under hard throttle. Nothing at idle, a little at upshift, seems to be a little more when it's cold. Haven't driven it much, but averaged about 14.5 MPG on mixed use - towing and no towing hiway/city.

I know Diesels smoke, never owned one before but had several big gassers. Is this normal (I'm thinking yes)? Several years ago I helped my Dad install the Banks kit on a Cummins so I know a little about tuning Diesels. I probably won't do much besides maybe the exhaust and intake. Might put a turbo on if I can find an inexpensive one, but in reality this is a 'tweener truck. I'll get newer in a few years. What simple things can I do to reduce the smoke? Do I want to eliminate it completely on this year/model?

Thanks for the help,

Steve

ps. I'm also trying to figure out the rear end. Can't find a tag, but the plate on the door says 45 under the axle portion of the sticker. Assuming it's stock, does that mean the 4:53 ? It is geared pretty low. I use to have a 3/4 ton with the straight 6 and 4 speed manual stump puller, this seems pretty similair.

 

That amount of smoke is absolutely normal. Dont worry about that amount of smoke.

You probably have 4.10 gears, but I dont know.

 

a 45 axle code is a 4.10 non limited slip.

 

Thanks for the replies. I figured the smoke was normal, but it's my first Diesel so just checking.


Thanks also for the help with the axle code. I've always heard limited slip differential before. I gues I'm not really sure what the non-limited slip is. Anyone care to give me a brief explanation?

Aprreciate the information,

Steve

 

the limited slip has a clutch assy that will drive the opposite wheel when one loses traction. in your axle, only one wheel drives.
you think it smokes now, wait til you pull a heavy load up a steep hill

 

Oh, I get it. I've always thought of that as a "normal" just plain rear end. Never heard it called a non-limited slip, but I get his meaning now. I was thinking the opposite that it was something like a locker rear end.

I've towed 7000 lbs up a 3 mile 6-7% grade and didn't think it smoked much, but then again I was babying it being a new (to me) truck and all.

I modified the intake by removing the soup bowl and moving the scoop down in front of the radiator (Thanks Ziggster). I'll see if it does better. Also thinking about getting a new 3.5" exhaust. Any thoughts on whether the exhaust upgrade is worth it? I've seen the sites about turning up the Injector pump, but I'm not sure if I want to do that as it's still smoking and that will probably make it much worse without a lot of gain, especially before I get the exhaust. Any thoughts?

Anybody know where to get an EGT gauge without having to pay $150?

Thanks,

Steve

 

Yeah "non-limited-slip" = open diff....

You're well on your way starting with the intake mods. Now give all that incoming air a good way to get out (bigger exhaust) and you'll definitely see some gains. Probably see less smoke too - especially if the smoke is black (excess fuel). If that's the case, turning up the fuel will make it worse until the intake & exhaust mods let enough air in and out to go with the fuel.

You definitely don't want to turn the fuel up until you have a pyro installed. eBay is a good place to look for inexpensive ones - both new and used....

 

Thanks Cheaper. Looking at your post I see on the bottom the dual air intake comment. I was thinking about doing this as well. The mod I made was easy enough so why no put in 2 intakes, one on each side of the radiator? I saw 2 problems: Where do you get an air cleaner with 2 snorkels tall enough for the cleaner? Did you just fabricate it? Also, the aluminum ducting I used might be kind of tight against the hood on the left side of the engine. Then again, with 2 intakes, a narrow or constrained section probably isn't too bad.

Does anybody have experience with Hypermax? They are about the cheapest 3.5 exhaust I could find. I know cheap usually ='s problems, but it's an exhaust, how bad can it be?

Steve

 

Take a look in my gallery for how I did my dual ram-air. I kinda' "colored outside the lines" on that one....Might want to take a look at the custom Y-pipe I did for my exhaust too, while you're there.

 

Excellent, thanks for the pics. I hadn't thought about getting another and cutting it. My '93 is a little different, but the end result is the same. Great idea. The intake around the engine and radiator will be different, but I'll see what I can do.


Thanks

 

Does the '93 have the openings in the bumper? Always thought those looked like prime candidates for ram-air intakes

 

No, the intake was right along the top of the grill between the radiator and the left headlight. It was a plastic peice about an inch high, 8 inches wide. The hood closed down on it, can't see how it got much air. Found a local guy parting out an F250, may call him and see about getting is air cleaner to chop up.