New trans
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New trans
Hi everyone,
I have a 1988 F-250HD 2x4 with an EFI 351W. I tow a 24' 5th wheel in Colorado. This truck is great but I need it to tow more efficiently and, if possible, get better than 11 mpg. It has a 3 speed auto trans in now. I'd like to put a super duty 5 speed with O/D. I would like to know what trans would fit? Any modifications that may need to be done? And will it make a big enough difference in drivability and mpg?? Thanks for the help.
I have a 1988 F-250HD 2x4 with an EFI 351W. I tow a 24' 5th wheel in Colorado. This truck is great but I need it to tow more efficiently and, if possible, get better than 11 mpg. It has a 3 speed auto trans in now. I'd like to put a super duty 5 speed with O/D. I would like to know what trans would fit? Any modifications that may need to be done? And will it make a big enough difference in drivability and mpg?? Thanks for the help.
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I'd love to go to a diesel but I'm on way to tight of a budget. My thought is that if the motor is running at its best, throw a set of headers on and give it a few more gears to run though, then I might be able to get even 15-17 mpg, not towing. Am I dreaming with that thought process??
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From: Trenton, MI
I'd love to go to a diesel but I'm on way to tight of a budget. My thought is that if the motor is running at its best, throw a set of headers on and give it a few more gears to run though, then I might be able to get even 15-17 mpg, not towing. Am I dreaming with that thought process??
My 95 F250 4wd was only get 9-10 in city and 11 mpg on hwy with 4.10. It had E40D.
Got tired of fill gas tanks so often. I swap 4.10 with 3.55 now I can get 14 mpg in city and 15-16 mpg hwy but that not worth to me.
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i'm pretty sure i've got 3.55 gears. this truck is my every day vehicle and I watch my RPM's sit at 3K doing 65mph. I think two more gears would really help with the milage. My goal is to drop a reman 351W with headers, maybe a better intake and a 5 speed trans. Hoping for 15-17mpg. But its a lot of $ and work so I want to be sure that what I'm doing will bring the results I need.
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Hi everyone,
I have a 1988 F-250HD 2x4 with an EFI 351W. I tow a 24' 5th wheel in Colorado. This truck is great but I need it to tow more efficiently and, if possible, get better than 11 mpg. It has a 3 speed auto trans in now. I'd like to put a super duty 5 speed with O/D. I would like to know what trans would fit? Any modifications that may need to be done? And will it make a big enough difference in drivability and mpg?? Thanks for the help.
I have a 1988 F-250HD 2x4 with an EFI 351W. I tow a 24' 5th wheel in Colorado. This truck is great but I need it to tow more efficiently and, if possible, get better than 11 mpg. It has a 3 speed auto trans in now. I'd like to put a super duty 5 speed with O/D. I would like to know what trans would fit? Any modifications that may need to be done? And will it make a big enough difference in drivability and mpg?? Thanks for the help.
Drivability? IMO always easier with an auto.
MPG? If you are hoping to go from 11mpg to 17 towing, I think you are in for a disappointment.
Mods: Clutch/brake pedals, hydraulic clutch, flywheel, cross member, possible TC relocation, possible DS mods.
Last edited by 85e150; Aug 19, 2011 at 02:17 PM. Reason: remove error. going blind I guess.
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He has a 4x2 so would need to look for a ZF5 from a `91 or earlier truck to get the speedo connection on the tailshaft.
Probably would get a useful MPG increase but at the cost of the PITA manual shifting.
Probably would get a useful MPG increase but at the cost of the PITA manual shifting.
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Look for a ZF trans from beind a 351w in F250s, F350s of your vintage. There was a change to electronic speedo somewhere around there, so watch for that.
Drivability? IMO always easier with an auto.
MPG? If you are hoping to go from 11mpg to 17 towing, I think you are in for a disappointment.
Mods: Clutch/brake pedals, hydraulic clutch, flywheel, cross member, possible TC relocation, possible DS mods.
Drivability? IMO always easier with an auto.
MPG? If you are hoping to go from 11mpg to 17 towing, I think you are in for a disappointment.
Mods: Clutch/brake pedals, hydraulic clutch, flywheel, cross member, possible TC relocation, possible DS mods.
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PITA manual shifting??
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Got cha!! The motor has almost 200k on it. The previous owner let it sit for two years and drove it with a bad cat converter. the engine needs either an entire rebuild or replaced. Personally, I'd rather replace it with a Ford reman with a warranty! So, I'd need to get the flywheel, clutch and starter for the ZF5 to work? Do you think there would be any other mods needed to make it work?
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You would need a flywheel and starter but you would probably want to get a new clutch kit and throwout bearing. You would also need the pedal assembly (with clutch pedal and master cyl) from a `91 or earlier truck. For appearance sake you might also want to swap in a steering column from a manual.
Not sure but you might need the manual cross member.
Plenty of guys here have done the manual swap (though most from the E4OD auto) so hopefully some advice from them will follow.
It shouldn`t be that hard to do as everything is bolt in and as you are starting with a C6 you will have no problems with your stock computer. You would just need to rewire the neutral safety switch and the backup lights (easy).
Not sure but you might need the manual cross member.
Plenty of guys here have done the manual swap (though most from the E4OD auto) so hopefully some advice from them will follow.
It shouldn`t be that hard to do as everything is bolt in and as you are starting with a C6 you will have no problems with your stock computer. You would just need to rewire the neutral safety switch and the backup lights (easy).
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You would need a flywheel and starter but you would probably want to get a new clutch kit and throwout bearing. You would also need the pedal assembly (with clutch pedal and master cyl) from a `91 or earlier truck. For appearance sake you might also want to swap in a steering column from a manual.
Not sure but you might need the manual cross member.
Plenty of guys here have done the manual swap (though most from the E4OD auto) so hopefully some advice from them will follow.
It shouldn`t be that hard to do as everything is bolt in and as you are starting with a C6 you will have no problems with your stock computer. You would just need to rewire the neutral safety switch and the backup lights (easy).
Not sure but you might need the manual cross member.
Plenty of guys here have done the manual swap (though most from the E4OD auto) so hopefully some advice from them will follow.
It shouldn`t be that hard to do as everything is bolt in and as you are starting with a C6 you will have no problems with your stock computer. You would just need to rewire the neutral safety switch and the backup lights (easy).
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From: Charles Town, W bygod Va
the auto trans that will work and have od would be an e4od, which is computer controlled, so you'd have that to deal with. The other option would be a gear vendor's overdrive and it will give you OD in all 3 of your gears making it a 6 speed. Both are going to cost some $$$. I'd be doing the math to figure out how long it will take to recoop the investment, a couple thousand dollars will buy a whole lot of gas.
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Well, that changes the picture completely. We all thought you were talking about doing a swap to a manual 5 speed.
The problem with a 5 speed auto is that you would have to swap in the engine as well with all the electronics that go with it including the PCM (computer). Getting the electrics to work would be a nightmare. Apart from anything else you would have no vehicle speed sensor for either the speedo of the trans.
You would need to fabricate new motor mounts and trans mount.
Your best option, I would think, would be to look for a bolt on overdrive unit for the C6.
The problem with a 5 speed auto is that you would have to swap in the engine as well with all the electronics that go with it including the PCM (computer). Getting the electrics to work would be a nightmare. Apart from anything else you would have no vehicle speed sensor for either the speedo of the trans.
You would need to fabricate new motor mounts and trans mount.
Your best option, I would think, would be to look for a bolt on overdrive unit for the C6.