upgrading 3speed manual to c4 auto 68 f100
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upgrading 3speed manual to c4 auto 68 f100
[font size="1" color="#FF0000"]LAST EDITED ON 29-Aug-00 AT 01:14 AM (EST)[/font][p]I have a 68 F-100, 240-I6 with a 3 speed tranny on the column. My wife has a tough time driving this rig and I'd really hate to sell it (have it in the paper, but trying to convince her otherwise). She is not very tall and has difficulty reaching the pedals to push the clutch in all of the way.
Is it fairly reasonable to upgrade this truck to:
PowerSteering (from donor through '79)
C4-Automatic.
I know that it would require at least:
1- C/4 Automatic tranny
1- New Radiator (with auto coolant tubes)
1- Gear ratio change of the 9" rear-end
1- Powersteering components & new column.
Am I crazy to try it (too expensive)? Or would I just be better off going to a different rig with the options?
The sad thing is that it is in excellent shape and the engine was rebuilt about 15,000 miles ago.
Photos at www.livinghope4u.com/f100
Is it fairly reasonable to upgrade this truck to:
PowerSteering (from donor through '79)
C4-Automatic.
I know that it would require at least:
1- C/4 Automatic tranny
1- New Radiator (with auto coolant tubes)
1- Gear ratio change of the 9" rear-end
1- Powersteering components & new column.
Am I crazy to try it (too expensive)? Or would I just be better off going to a different rig with the options?
The sad thing is that it is in excellent shape and the engine was rebuilt about 15,000 miles ago.
Photos at www.livinghope4u.com/f100
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upgrading 3speed manual to c4 auto 68 f100
you are partially correct. you will need the tranny. and the power steering components and column. but as far as the radiater yo do not have to change that. all you need is an aftermarket trans. cooler.($50) wich is actually better than the stock radiator one. why would you need to change the rear end gears? there wont be a problem with them. alltogetheri would say if you are getting as much of the stuff as you can from a junkyard you will spend $400-$500 dollars.
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upgrading 3speed manual to c4 auto 68 f100
That's great to hear on the tranny cooler... A few more questions:
1) Won't I run into problems with different gearing in the 3rd member between a 3-speed manual and the C-4? Were they the same, or will it be 'close enough'? I haven't looked at the tag on the 3rd member yet.
2) Will the driveline length be the same between the C-4 and the 3 speed, or will that need to be changed as well?
3) Does a tranny kickdown need to be added to the carb?
4) Will there be any tranny mating issues between the 240-6cyl and the C-4? (Does the flywheel need to be changed; will the setup 'bolt up'?)
>Wade Anderson
1968 F-100
240 6cyl
3-speed column shift
115,000 Original Miles
1) Won't I run into problems with different gearing in the 3rd member between a 3-speed manual and the C-4? Were they the same, or will it be 'close enough'? I haven't looked at the tag on the 3rd member yet.
2) Will the driveline length be the same between the C-4 and the 3 speed, or will that need to be changed as well?
3) Does a tranny kickdown need to be added to the carb?
4) Will there be any tranny mating issues between the 240-6cyl and the C-4? (Does the flywheel need to be changed; will the setup 'bolt up'?)
>Wade Anderson
1968 F-100
240 6cyl
3-speed column shift
115,000 Original Miles
Fleet Owner
Joined: Jun 1999
Posts: 24,552
Likes: 74
From: Creedmoor, North Carolina
upgrading 3speed manual to c4 auto 68 f100
Wade the swap should be fairly simple. It would much more problematic to go the other way. I'll try to help with your questions.
1- The gearing between the straight and auto was .25 when I last checked. Your truck likely has a 3.75 rear and an auto would have 3.50. So you engine will turn a little faster at 60 mph. than it does now.
2- Grab the driveshaft with the tranny, then the ends should mate up.
3- You will need the kickdown if you expect the passing gear to work.
4- The auto uses a flexplate rather than a flywheel, so grab that as well. You will have to remove the pilot bearing off the crankshaft too.
If you don't know the history of the tranny you may want to rebuild it before the installation.
good luck,
John
jowilker@nc.freei.net
66 F100s
In the still cool hours of the night, you can hear chevys rusting away.
1- The gearing between the straight and auto was .25 when I last checked. Your truck likely has a 3.75 rear and an auto would have 3.50. So you engine will turn a little faster at 60 mph. than it does now.
2- Grab the driveshaft with the tranny, then the ends should mate up.
3- You will need the kickdown if you expect the passing gear to work.
4- The auto uses a flexplate rather than a flywheel, so grab that as well. You will have to remove the pilot bearing off the crankshaft too.
If you don't know the history of the tranny you may want to rebuild it before the installation.
good luck,
John
jowilker@nc.freei.net
66 F100s
In the still cool hours of the night, you can hear chevys rusting away.
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upgrading 3speed manual to c4 auto 68 f100
Thanks on your helpful information. With all that I am planning on doing, I'll probably see if a donor truck is available. That is bound to be less expensive than purchasing the parts separately & I could sell off any other items.
One last question:
Does the whole setup have to be off of a 6 cyl, or can I get away with it being off of a small block with a C-4? Or will I run into driveshaft length differences between the I-6 and a SB V-8?
>Wade
1968 F-100
240 6cyl
3-speed column shift
115,000 Original Miles
One last question:
Does the whole setup have to be off of a 6 cyl, or can I get away with it being off of a small block with a C-4? Or will I run into driveshaft length differences between the I-6 and a SB V-8?
>Wade
1968 F-100
240 6cyl
3-speed column shift
115,000 Original Miles
Fleet Owner
Joined: Jun 1999
Posts: 24,552
Likes: 74
From: Creedmoor, North Carolina
upgrading 3speed manual to c4 auto 68 f100
Wade, The big difference here would be the kickdown. The carb on a V8 is in the center top, and the I6 is off to the side.
I believe that the 351, 302, and 240/300 I6 use the sane tranny bolt pattern.
I changed out the two piece driveshaft for a single shaft and took it to driveshaft shop for correct sizing.
John
jowilker@nc.freei.net
66 F100s
In the still cool hours of the night, you can hear chevys rusting away.
I believe that the 351, 302, and 240/300 I6 use the sane tranny bolt pattern.
I changed out the two piece driveshaft for a single shaft and took it to driveshaft shop for correct sizing.
John
jowilker@nc.freei.net
66 F100s
In the still cool hours of the night, you can hear chevys rusting away.
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New User
Joined: Aug 2000
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upgrading 3speed manual to c4 auto 68 f100
Thanks! It looks like I can get the parts locally for about $600, with the steering box being brand new.
1968 F-100
240 6cyl
3-speed column shift
115,000 Original Miles
1968 F-100
240 6cyl
3-speed column shift
115,000 Original Miles
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