thesuperbad234

Alright guys, my truck is drinking gas like its beer, and I cant figure out why. It's a 95 f150 5.0 4x4 with 4.10 gears, headers, 32x11.50s, a hypertech chip, 5 speed manual, k&n drop in, and fresh fluid/plugs wires cap and rotor in EVERYTHING. I can barely get 10 highway driving (I'm lucky to get 150 miles out of my front tank) I drive it nice, don't pass often, and the overdrive keeps me at about 2500 rpms at 65mph. What ticks on these trucks that causes such terrible mileage? I've witnessed trucks with 6 inches and 35s get the same mileage I'm getting right now. Any ideas??

fltdriver

It's your gearing, 4.10 is for low end power (big tires, lots/heavy hauling), I've got 3.55 with a 5.8 and just checked my mpg's yesterday-came in at 13.6mpg with a little less than half of it highway and the truck idling with the AC on for at least 30 minutes on that tank.

IMO chips don't work unless they have been programmed/tuned specifically for your setup by a shop. Most of the ones that offer more HP just decrease the fuel/air ratio burning more fuel to offer slightly more power. If you are serious about trying to get better MPGs then here are some options:
E-fan conversion: I followed unit505's lead and got a mopar fan from JY, $20 controller, and installed for under $75 total. Highly recommend this as it takes away the airplane sound of the engine.
Check for vacuum leaks and pull your codes.
Pull your codes.
Clean the TB blades.
Ensure brakes aren't dragging and repack/replace all of you wheel bearings.
Timing bump to 11-12*BTDC
Find a 3.55 or 3.73 rear end to swap in.
Take the chip out.


With the 302 you should be able to get 17mpg highway fairly easily and without re-doing the rear end, a regear job could get you close to 20 but you would probably need stock size tires to do that.

BLDTruth

I agree with everything fltdriver said.

For a reference, mine is a 1994 F150 5.0 4x4 5-speed manual with 31x10.5's and 3.55's. I also have fresh plugs, wires, cap, rotor, k&n drop in, and fresh fluid in everything (within last 3 months). At 65mph it sits at ~2100 rpms. I average about 13-14 mpg with 50/50 city/highway. But I can get ~18mpg if I drive 55-60mph for long distances on the highway.

thesuperbad234

The previous owner put the chip in, do I have to replace it with something or can I just pull it out and call it good? I also have no idea where its located, so that would be a big help too. I haven't gotten a check engine light, and my bearings were repacked about 2 months ago, I think my rear brakes may be dragging a bit, I've been wanting to do the timing bump for some time now, but haven't gotten around to buying all the new parts to do it. Ignition coil, cap and rotor, copper core plugs, etc.. How hard was it to do the e fan conversion? And do you have a link to somewhere that could show me how/what parts to order for it? I'd happily do it if i could get away with it for less than $75, smog pump delete and underdrives are also a soon to come. Lastly, What would it improve/effect by pulling the chip? Sorry about all the questions, Just really curious!

Modular man

If u want to go cheap just go to a junkyard and get the fan or Craigslist. I took mine out of 90s model mustang lol it fit perfect . Then just go to ur local parts store and get the controller .there's also a lot of videos on YouTube that walk u threw it dnt expect a big jump in mpg but u will get sum and sum torgue

Crownman

You don't have to buy all that stuff just to do a timing bump. Just check the stuff you have. If it's still in good shape then bump it a little.

As far as the chip goes. There's no telling if you can just pull it or not. You have no idea what parameters it's changing. It could already have the timing bumped. If it's a performance chip then I'm guessing it might already. If ti does and you bump the base timing up you might get horrible detonation. My suggestion, get in touch with the previous owner and ask him exactly what's programmed on the chip.

Doing the Efan conversion can be done for less than $75 if you are willing to do the footwork at a junkyard and put in the time to piece the system together.

If you remove the smog pump you need to remove the tubing and plug the port in the back of each head. Also, if you still have the stock catalytic converter in the truck then you need to leave the smog pump on there. The smog pump provides fresh air to the cat.

thesuperbad234

Well the previous owner is actually dead so.. Yeah haha. I've been wanting to do the six litre tuneup, and I tried looking up a controller but they wanted like $300! So any tips on what to collect for less than $75 would be great. I'll probably leave the smog pump on there just won't run the belt on it. My cats already taken out and I had to cut the tubing out of it when I put my headers on cause they got in the way. Would underdrives actually do me any good or is it not worth my time?

Crownman

Take the 150 youd spend on underdrive pulleys and add it to the 75 for the efan. You can get a flex a lite 31163 setup for 180 and a fan for 20 bux at a junkyard. I use that controller with a fan from a mid 90s thunderbird and it works great. The efan swap will free up more hp than any undrive setup ever would on these trucks.

Since you cant find out from the previous owner what programming is changed on the chip you need to find a mustang performance shop that can program early mustangs which basically used the same chip. They will be able to read it and tell you whats been done. You need this info before bumping timing or messing with any engine control stuff.

If the smog pump isnt doing anything the get an old one from the junkyard for 5 bux and take the guts out. Then you have a cheap idler pulley and you can keep the correct belt.

Chris_1

iTrader: (1)

You think your brakes are dragging a bit and you're wondering how to get better gas mileage ? Fix your brakes would be #1 on the list.

fltdriver

http://www.autozone.com/cooling-heat...at/267187_0_0/

That's the controller I have, $17.99 at AZ. Every auto parts store carries them, just ask for a Cooling fan Temperature controller, the cheapest one they have. You don't need any fancy bells or whistles.

Here is a thread from a while ago dedicated to the swap, pretty long thread though.
https://www.f150forum.com/f10/electric-fan-swap-152094/

This is a thread that I made as I was doing the swap, disregard post #6 as I tried to overthink the process and came up with a "new" idea that didn't work.
https://www.f150forum.com/f10/e-fan-conversion-273073/