Hey guys I'm looking at picking up a 93 F350 4x4 crew cab (NOT a DUALLY) it has a 5.8 H.O. (351) auto only has 50K mls on it, What kinda MPG should i expect and is there any thing i should be weary of ? Thanks DW

 

I have a '93 3/4 ton Extra Cab with the 5.8, E4OD and 3.55 gears I do almost exclusively city driving and get about 10. I tried babying it for one tank and got 10. I towed my buddy's Mazda P/U on a car hauler for part of 1 tank (pretty flat ground) and got 10.

I included the info about my tranny and gears because those seem to be important factors as well. If you do a search, you'll find lots of good info.

 

my f-250 with 5.8 auto c-6 trans.4x4 3.55 gears has never gotten over 10 mpg loaded empty or towing my boat,also doesnt ever feel like it has enough power for the engine size kinda doggy on the hills especially towing

 

My truck is very similar to what you are looking at: '92 F350 single rear wheel Crew Cab 4x4, 351, C6, came with 3.55 gears stock, has 33" tires.

With that combination I was getting about 12 on a flat highway unloaded, 10 in normal driving, and alot less when loaded or driving up hills.

Like Markb said, it was a real dog when loaded or going up hill. I really had to stick my foot in it and it lost alot of speed on hills even when unloaded, and all this wide open throttle sucked up alot of gas.

I changed it to 4.56 gears and now it has substantially more pulling power and gets better mileage on hilly roads and when loaded. On my first trip to the desert going my usual route (over the mountains), I got about 3 more mpg with the new ratio. I was driving 2-lane highway and keeping the speed down to 60mph or less. On the freeway, with no overdrive in the trans, it sucks up alot of gas if I try to go over 65mph.

I would search for a truck that already has 4.10 gears in it, if you plan to keep the stock size tire on it, as gear changes are not cheap (mine was $1650 + tax for front and rear gears and a locker in the rear), and you will no doubt be disappointed with the lack of power with that 351/3.55 gear combo in that heavy truck (mine weighs ~6500 lbs unloaded in normal driving) if you do any towing or driving in the mountains.

If you plan to run 35" or bigger tires, then it doesn't matter what gear ratio it has now as you will be wanting to change it anyways to 4.56 or lower (numerically higher). With 33's you can use 4.10 and be ok, even though 4.56 would be better, since you have overdrive, but if you can get the 4.10's for free (in the truck already when you buy it), go with that. With stock size tires, 4.10's are very good.

[On Edit:] Excuse me, I misread your post and thought you were looking to buy that truck, which is why I suggested look for one with a different gear ratio. Now I see that you already have the truck. Sorry about the mis-read.

 

yup i bought it, and have already ordered the 4.56 gears for the front and rear plus a eaton locker for the rear, also putting on it 16x10 wheels and 305 70 16 nitto tera grappler tires, there like a 33 12.50 plus i just ordered a venders gear drive unit which will give me .78 overdrive, so think that combo should do okay. or i hope at least. DW

 

Wow, that sounds like a great combination!! How much was the Gear Vendors OD? I would like to have one in mine . Let me know how it works when you get it all installed. It will be a while before I can afford one, unless I find one used, which isn't very likely as they are made specific to the transfer case or transmission they mate to. Gear Vendors is right out here by me in the SanDiego area too. El Cajon if I remember correctly.

 

I get 10mp on an 88 Crew w/351 (& C6?). It has Ladder rack and tailgate stays up. Normally 60mph on interstate with little town driving. I babied it for 1 tank and got 11. I should pull the rack and drop the gate to gain a little

 

Gear vendors is REALLY expensive. Yeah, you get more gears and overdrive, but the unit alone is $2495 for my t-18, plus installation. I can buy a lot of gas for that. Or a ZF 5 speed. Maybe two of them.