Gary Lewis Posted October 31, 2022 Author Share Posted October 31, 2022 Well, I recently got back from a 3000-mile road trip in the 86 Bronco! I have been tracking mileage on long road trips for a while. I have a similar trip from a few years ago tracked, and I compared the mileage. The Edelbrock Pro-flo 4 EFI system gets me 10% better MPG than the OEM ford EFI system on the same 5.0l engine. I think it would have been even better if we hadn't had to fight a headwind across the whole state of South Dakota! I'm waiting on delivery of a 4r75w transmission from Monster Transmission now. I'll be replacing my old AOD with the new electronically-controlled one. I'm sure I'll see great improvements with that too! I'll be sure to post about it when the trans comes! In the meantime, my shop is covered in sawdust because I'm making built-in bookshelves that my lady wanted for the house. :D Wow! 10% is good when you probably started with good MPG anyway. But could you give us some #'s? What was it and what is it now? But why do you think you'll get much better MPG with the new tranny? My understanding is that the AOD has a .67:1 OD and the new one has a .70. So you'll be turning slightly more RPM, although not much at all. But should be able to stay in OD longer. Anyway, just curious. Link to comment Share on other sites More sharing options...
Nickelplate Posted October 31, 2022 Share Posted October 31, 2022 Wow! 10% is good when you probably started with good MPG anyway. But could you give us some #'s? What was it and what is it now? But why do you think you'll get much better MPG with the new tranny? My understanding is that the AOD has a .67:1 OD and the new one has a .70. So you'll be turning slightly more RPM, although not much at all. But should be able to stay in OD longer. Anyway, just curious. Neither mileage is actually that great. The old trip was 10.717 MPG and the latest trip was 11.848. If I take away the leg of the trip where there was like a 40mph headwind, the average for the new trip would be 12.705. The new trip also had me towing a small trailer containing our camping gear, so that probably made a bit of a difference. The new transmission should give improved fuel mileage because The electronic control of the shifting makes things a bit more efficient, the ratio of the lower gears gets the vehicle to OD speeds quicker, the different OD ratio means the vehicle stays in OD more than with the AOD, and the improved torque converter design means that the vehicle coasts more freely than with an AOD. On the AOD, I coasted downhill and still decelerated! Link to comment Share on other sites More sharing options...
ArdWrknTrk Posted October 31, 2022 Share Posted October 31, 2022 Neither mileage is actually that great. The old trip was 10.717 MPG and the latest trip was 11.848. If I take away the leg of the trip where there was like a 40mph headwind, the average for the new trip would be 12.705. The new trip also had me towing a small trailer containing our camping gear, so that probably made a bit of a difference. The new transmission should give improved fuel mileage because The electronic control of the shifting makes things a bit more efficient, the ratio of the lower gears gets the vehicle to OD speeds quicker, the different OD ratio means the vehicle stays in OD more than with the AOD, and the improved torque converter design means that the vehicle coasts more freely than with an AOD. On the AOD, I coasted downhill and still decelerated! Can I ask, what's your tire diameter with the 4.55's? I know 302's need to rev. 12mpg seems fair with that much air under the truck! Link to comment Share on other sites More sharing options...
Gary Lewis Posted October 31, 2022 Author Share Posted October 31, 2022 Can I ask, what's your tire diameter with the 4.55's? I know 302's need to rev. 12mpg seems fair with that much air under the truck! I didn't catch that you are running 4.55's, but even with 33" tires you are only turning about 2000 RPM at 65 MPH in OD. I'd think that the 302 will pull pretty good at that, but might have to shift out of OD on climbs, especially pulling that trailer. And pulling that trailer would certainly drop the MPG some, so 12 isn't too bad. Link to comment Share on other sites More sharing options...
Nickelplate Posted October 31, 2022 Share Posted October 31, 2022 I didn't catch that you are running 4.55's, but even with 33" tires you are only turning about 2000 RPM at 65 MPH in OD. I'd think that the 302 will pull pretty good at that, but might have to shift out of OD on climbs, especially pulling that trailer. And pulling that trailer would certainly drop the MPG some, so 12 isn't too bad. I'm actually running 3.55's and never updated the signature... sorry. And they are 31-inch tires. I monitored various RPMs and such during the trip. In OD, I was running like 1700RPM at 70mph. about twice that with OD off. Link to comment Share on other sites More sharing options...
Nickelplate Posted October 31, 2022 Share Posted October 31, 2022 I'm actually running 3.55's and never updated the signature... sorry. And they are 31-inch tires. I monitored various RPMs and such during the trip. In OD, I was running like 1700RPM at 70mph. about twice that with OD off. Another thing I noticed on the trip that I'm going to change is that the road noise from the mud tires was terrible, and those old cyclone wheels are unable to be balanced any better than they currently are. They cause a little bit of vibration that ended up being annoying after a while. I think I'm going to get some new wheels and some tires with way less aggressive tread on them. Link to comment Share on other sites More sharing options...
Gary Lewis Posted October 31, 2022 Author Share Posted October 31, 2022 Another thing I noticed on the trip that I'm going to change is that the road noise from the mud tires was terrible, and those old cyclone wheels are unable to be balanced any better than they currently are. They cause a little bit of vibration that ended up being annoying after a while. I think I'm going to get some new wheels and some tires with way less aggressive tread on them. Our calculator says you should be running about 1800 RPM at 70 in OD and 2700 in 3rd. That 1700 is probably too low for the 302 to have much torque, and it may shift out a lot. Hopefully you can tune the controller with the new tranny to keep it in longer, which will help your MPG. As for the tires, I like my Wildpeak AT3W's. Far lower noise than the old tires, and a lot less weight needed to balance them. Link to comment Share on other sites More sharing options...
ArdWrknTrk Posted October 31, 2022 Share Posted October 31, 2022 I'm actually running 3.55's and never updated the signature... sorry. And they are 31-inch tires. I monitored various RPMs and such during the trip. In OD, I was running like 1700RPM at 70mph. about twice that with OD off. No need to apologize. I was just interested in what kind of revs you were turning on a 3k trip. 3.55's make more sense... Link to comment Share on other sites More sharing options...
scbill Posted October 31, 2022 Share Posted October 31, 2022 No need to apologize. I was just interested in what kind of revs you were turning on a 3k trip. 3.55's make more sense... Another FWIW comment, 4.9/AOD 215/75/15, 87" circ 1800rpm@70 MPH, 11/12 MPG. Haven't been far enough trip to check trip mileage. Link to comment Share on other sites More sharing options...
Gary Lewis Posted October 31, 2022 Author Share Posted October 31, 2022 Another FWIW comment, 4.9/AOD 215/75/15, 87" circ 1800rpm@70 MPH, 11/12 MPG. Haven't been far enough trip to check trip mileage. I guess I'm feeling better about getting ~12 MPG with Big Blue. I keep thinking a 300/AOD combo should be in the high teens. David/1986F150Six got ~20 with his 300/4-speed with OD combo. But he drives right at 65 MPH and like the grandfather he is, so... Link to comment Share on other sites More sharing options...
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