I'm back !!!

[Gary Lewis]

I agree that fuel mileage has improved very little, but then I am reminded that my 1986 F150 with 4.9L engine which could achieve 25+ MPG on the highway weighed ~3750#. Today, a F150 weighs 5000+# with much more power.I would like to have a 2.7L Ecoboost in a 3750# truck and see what gas mileage that would return.

Blue, my 2015 F150 with a 3.5L EB and Max Tow package, gets about 18 MPG average. We just drove it over 3000 miles at usually 80 MPH and got that. But if you back off and drive it 65 MPH w/o cruise it'll get more like 20 MPG. And if you drive it 55 MPH it gets over 22 MPG.

 

That Max Tow package means it has the same tow rating as Big Blue - 12,000 lbs. But it'll tow so much easier than Big Blue. In fact, on our 2500 mile tow of the 25' Sea Ray boat to Lake Powell and back we got 11.0 MPG, which is what Big Blue got without a trailer before the EFI system was installed.

 

Part of the Max Tow package is 3.55 gears, so if you stayed with the stock 3.23 gears and went with the 2.7L EB you'd be much better in MPG.

[Squirlye]

Thanks guys, I'll try to check all of these thing this weekend if I get the chance. I actually have a combustion leak tester, so I'll use that to see if it's a head gasket. And while I'm at it I'll will check my compression in each cylinder. I've been wanting to do that for awhile. And I'll check for vacuum leaks as well. I will use a vacuum gauge to see if it's pulling the correct amount of vacuum. I've heard about the smoke test before, but I don't like cigars or cigarettes. So I will have to make a smoker of some kind. And I have already tried spraying carb cleaner to check for leaks. Ive never heard a change in the idle. But I'll try again. And while I'm at it, I'll pull the carb and give it a good once over. Hell I might even change the oil, it's probably getting close to that time anyway. Also I might have forgotten to mention that when i installed the HEI I deleted the whole computer system. So thanks again for the help. I will report back with my findings this weekend.

[Gary Lewis]

Thanks guys, I'll try to check all of these thing this weekend if I get the chance. I actually have a combustion leak tester, so I'll use that to see if it's a head gasket. And while I'm at it I'll will check my compression in each cylinder. I've been wanting to do that for awhile. And I'll check for vacuum leaks as well. I will use a vacuum gauge to see if it's pulling the correct amount of vacuum. I've heard about the smoke test before, but I don't like cigars or cigarettes. So I will have to make a smoker of some kind. And I have already tried spraying carb cleaner to check for leaks. Ive never heard a change in the idle. But I'll try again. And while I'm at it, I'll pull the carb and give it a good once over. Hell I might even change the oil, it's probably getting close to that time anyway. Also I might have forgotten to mention that when i installed the HEI I deleted the whole computer system. So thanks again for the help. I will report back with my findings this weekend.

Do you also have a leak-down tester? I've sworn off of compression testing as I've gotten poor results so many times. But leak-down testing will even tell you if you have a head gasket leak or a cracked head or block.

As for smoking, I don't think David smokes either. But a Swisher Sweet cigar doesn't have a horrible taste and a couple of puffs isn't likely to get you hooked.

And there isn't a "correct amount of vacuum". Each engine is different depending on the wear it has, how cold it is, the tune of the carb, the idle speed, the ignition advance, etc. In fact, a tiny leak can actually cause the vacuum to go up as most engines run faster with a small leak, and the faster an engine runs at the same throttle opening the more vacuum it'll pull. So the vacuum reading isn't a good test for if it has a leak or not.

[AmericanSavage]

Blue, my 2015 F150 with a 3.5L EB and Max Tow package, gets about 18 MPG average. We just drove it over 3000 miles at usually 80 MPH and got that. But if you back off and drive it 65 MPH w/o cruise it'll get more like 20 MPG. And if you drive it 55 MPH it gets over 22 MPG.

 

That Max Tow package means it has the same tow rating as Big Blue - 12,000 lbs. But it'll tow so much easier than Big Blue. In fact, on our 2500 mile tow of the 25' Sea Ray boat to Lake Powell and back we got 11.0 MPG, which is what Big Blue got without a trailer before the EFI system was installed.

 

Part of the Max Tow package is 3.55 gears, so if you stayed with the stock 3.23 gears and went with the 2.7L EB you'd be much better in MPG.

I have been meaning to ask this question for a while. I am completely ignorant on such matters.What kind of upgrades could one do to the drive train? Is there a 5 spd overdrive tans one could fabricate? Or would that also mean replacing the transfer and/or the rear end/front end?

[mat in tn]

I have been meaning to ask this question for a while. I am completely ignorant on such matters.

What kind of upgrades could one do to the drive train? Is there a 5 spd overdrive tans one could fabricate? Or would that also mean replacing the transfer and/or the rear end/front end?

the 4wd makes it a bit harder. the 2wd versions are much easier to modify in this way. im guessing that you have the c6?

[Rembrant]

I have been meaning to ask this question for a while. I am completely ignorant on such matters.

What kind of upgrades could one do to the drive train? Is there a 5 spd overdrive tans one could fabricate? Or would that also mean replacing the transfer and/or the rear end/front end?

5spd swaps are getting to be pretty common in the Bullnose trucks, even more so lately with the way fuel prices have been going. I have converted two Bullnose trucks to 5spds, one a 2wd, and one a 4x4. The Ford pickups got 5spds across the board starting in 1988. I believe the ZF5 showed up first in 1987, but only in the F350's, and even then only the diesels I think (maybe also the 460). Swapping a 5spd into a 2wd pickup is easier of course...less hardware to deal with, but the one downside to doing a 2wd swap is that you're more limited to transmission options due to the cable speedo drives. Since the 4x4 cable speedo drives were in the transfer cases, it means more availability for transmission donors (1988-1996).

[reamer]

I have been meaning to ask this question for a while. I am completely ignorant on such matters.

What kind of upgrades could one do to the drive train? Is there a 5 spd overdrive tans one could fabricate? Or would that also mean replacing the transfer and/or the rear end/front end?

5spd swaps are getting to be pretty common in the Bullnose trucks, even more so lately with the way fuel prices have been going. I have converted two Bullnose trucks to 5spds, one a 2wd, and one a 4x4. The Ford pickups got 5spds across the board starting in 1988. I believe the ZF5 showed up first in 1987, but only in the F350's, and even then only the diesels I think (maybe also the 460). Swapping a 5spd into a 2wd pickup is easier of course...less hardware to deal with, but the one downside to doing a 2wd swap is that you're more limited to transmission options due to the cable speedo drives. Since the 4x4 cable speedo drives were in the transfer cases, it means more availability for transmission donors (1988-1996).

I did the ZF-5 in my '86 4x4 Flareside, Original T-case pit perfectly, Only mod was relocating the cross member back... and Optional was to shorten the rear and lengthen the front shafts

[Squirlye]

I did the ZF-5 in my '86 4x4 Flareside, Original T-case pit perfectly, Only mod was relocating the cross member back... and Optional was to shorten the rear and lengthen the front shafts

So it's been almost a month since posting about my overheating issue. I didn't get to it until 2 days ago. So I picked up a combustion leak detector. And everything checked out. So no leaking head gasket, or it's not detecting it. The weird thing is after I checked it. I drove it to another town 31 miles away, and no problems. As a matter of fact, when the gauge got to the far side of the "N" the thermostat opened and it went back down. I'm wondering if it had an air pocket, and when I used the leak detector it removed the trapped air. I also checked the lower hose and it does not have a spring. I was going to flush out my cooling system in the future and replace all of the hoses. So I checked my new lower hose and it doesn't have a spring inside either. I guess I will have to drive it around on the freeway and see if it happens again.