I recently bought a 1994 ford f150 4x4 with a 302 v8 and I just have some questions. 1st my rear axle. The code says H9 which means I have a LSD but when I jacked up the back and spun a wheel the other one spun the different direction. So do I have a LSD or not. 2nd how bug are my tanks I heard they were 18 gallons but the seem smaller then that. 3rd my gas mileage has been really ****ty so my question is how could I improve that. I'm going to test all the emissions stuff to see if it needs replacing and I'm going to fix my exhaust leak to see if that helps(its pretty big) so any answers will help. Thanks.

 

1. Hard to tell on something old enough to buy booze. Could've been swapped out for an open diff long ago. Maybe it hasn't been taken care of.
2. If I recall correctly, you should have an 18 gallon front and 19 gallon rear tank unless you have an odd configuration. (The regular cab short box 4x4 only has the rear tank.) Or maybe it's 19 front and 18 rear, but I think it's one or the other.
3. There are volumes of posts on this question. Nothing specific to what you've mentioned here comes to mind, though. How do the plugs, filters and fluids look? You're not dragging a brake somewhere?

 

1. Open up the diff cover and see what's inside. The fluid ought to be changed anyway.

2. Very likely the fuel guage is saying empty when there are still several gallons in the tank. Try running one tank till the engine sputters, then see how many gallons will go in. Even then, there will still be one or two gallons of "unusable" fuel in the tank when it starts to suck air.

3. How many MPG are you getting?

 

1) ford trakloks aren't exactly known for the longevity. If it's the original it's probably just worn out. You can get rebuild kits for them and even make them better than stock.
2) there doesn't seem to be any ryme or reason to the tanks. Or the fuel gauges are way off. I've never got more than 16 in either of my tanks and that's running them well past the uneasy point.

 

Six liter tuneup. Just got it done here a week or so ago. Bumped my highway mileage, haven't checked city yet. But an improvement nonetheless.

 

What is the six liter tune up

 

That spin test for a limited slip is BS. Either believe the axle tag or door code, or open it up and look. Chances are, it's worn out anyways.

 

http://fullsizebronco.com/forum/showthread.php?t=63592

This is where I was directed to.

 

What trans and what size tires? I get roughly 16.8-18 with a 5.0 5 speed 3.55s on 31s.

 

Thanks everyone I will pull the diff cover and change my fluid and I was actually able to get the diff to work today. I'm running 30s with 3.55s and a 4 speed with overdrive and I've been getting around 15 I think.

 

15 mpg with a 4x4 302 V8 F150?

What were you thinking would be about right?

 

I was at 14ish highway until I did six liter tune. Jumped to 18.5 after. 94 f150 5.0 e4od.

 

I have this exact setup and I haven't measured exactly but I got about 19

apparently I did the six liter tune up before I knew what it was

 

I can only help with the fuel tank sizes - and my info comes from the 96 service manual. I assume the 94's are the same. ALL aft of axle tanks on 96 F150 and 250's are 18.2 gallons. Also, ALL 96 F150 4X4's mid ship tanks are 19 gallons (if it has a mid ship tank - the 116.8" wheel base does not have the second tank). So, your mid ship tank is 19 gal, and your rear tank is 18.2 gallons.

 

Don't forget, you need some diff oil that has limited slip additive in it.