Join Our Ford Truck Forum Today

Document your Ford truck project here and inspire others! Login/Register to view the site with fewer ads.

'68 F-100 5 Speed?

I just bought a 1968 F-100 with the 300 straight 6 and 4 on the floor. I was wondering if anyone could give me advice on a good 5 speed transmission.
 

1970Custom

They call me Spuds
14,107
447
Middleton, ID
300-6? I'd swap an M5OD out of the newer F-150...
 

Fellro

Moderator
Staff member
Or go for a ZF, pre 92 to have speedo drive.
 
I've heard of the M5OD. Would it be a direct fit? Or would the zf be easier? I like the truck as-is, but I currently use it as a daily driver and would rather not be at 4500rpm at 65mph. Thanks for the info.
 
Last edited:

Fellro

Moderator
Staff member
Both are direct fit to the motor, it is the cross member where things may change a bit, as in farther back, and drive shaft mods are almost certainly required. The M5OD is lighter duty, and as such has been known to fail, but as with anything how you use it will determine its longevity. If you don't tow or such, it should serve you well.
 

dustybumpers

don't play well w others
You have to watch the year of truck you get the transmission from.
starting in 92 the speedometer is electronic and there is no provision for a speedometer cable.
Also keep in mind the m5od and the ZF both use an interior hydraulic clutch pack, which means the unit is inside the transmission bellhousing and rides behind the throwout bearing.
You will need the Slave cylinder on the firewall, and the clutch pedal assembly inside that goes with it

as mentioned about the crossmember, the frame is a bit different, so some fab work is necessary
All in all, it is an easy swap, and well worth it
 

dustybumpers

don't play well w others
also, most 6 cyl trucks had the zf, most v8 had m5od. 5.0 and 5.8 will both bolt up

Make sure to get the driveshaft, you will need to shorten your driveshaft, and put the transmission end from the newer shaft on your shaft
 
Once again, thanks for the info. I'm leaning toward the M5 because it looks like they're cheaper. I don't plan on towing anything except possibly a 16ft aluminum hull. I've seen that there's a m5od, m5r1, and a m5r2. What's the difference and which would be better?
 

dustybumpers

don't play well w others
M5 od is first gen, that will be the one you need. it has a speedometer gear.Your cable hooks right up
r1 has a plate you can drill out where the speedo cable hooks up, and there is a gear in there. Some improvements, but not enough to worry about.
r2 has more improvements, they fixed the leak I was talking about, they improved the bushings for the shift tower, etc. very nice trans, but no good to you, because there is no way to hook up a speedometer cable
 

dustybumpers

don't play well w others
BTW, the ZF ts a bad azz trans, and although cost more, is well worth the money.
You can tell them when you look at them, they have PTO (power take off ) plates on them
 

dustybumpers

don't play well w others
Keep us posted, and let us know what you end up with.

Around here, a good ZF will run $12-1600
Watch for too much play in the head shaft. The way you tell, the whole front case will be wet with oil, Or if you happen to be lucky enough to drive it, it will "rattle" at an idle
 
I found a site that sells both in brand new condition. Once I decide on which I want, I'll get in touch with them for one.
smartpartsauto.com
 
Last edited:

DNFXDLI

The Token Canadian
Staff member
I've heard of the M5OD. Would it be a direct fit? Or would the zf be easier? I like the truck as-is, but I currently use it as a daily driver and would rather not be at 4500rpm at 65mph. Thanks for the info.

What gears and tires are you running?..that seems really high!
 
Not a clue on the gears. I believe the tires are stock. I was so busy having fun cruising around in it, I forgot to check before I came to work.
 
Not a clue on the gears. I believe the tires are stock. I was so busy having fun cruising around in it, I forgot to check before I came to work.

I bought a 61 chevy pu one time that someone had changed the
engine from a 6 to a 350 engine,but it was a auto trans.,My problem
I had with it was,any thing over 60 mph,it sounded like I needed
another gear.
I think the gear ratio in the rear end was matched for the 6 cyl engine,
an the spd of that era...So you might have to take that in consideration.:)
 

dustybumpers

don't play well w others
I found a site that sells both in brand new condition. Once I decide on which I want, I'll get in touch with them for one.
smartpartsauto.com

Keep in mind your going to need a lot of other stuff

Crossmember and trans mount
Front half of driveshaft
Clutchslave inside transmission and throwout bearing
hydro line
master cyl
clutch pedal and mount
There is also a firewall plate from 80-87 to stiffen the firewall, you will have to make something

I think the new transmission is a great idea, but you are still going to be saving some parts up
 
My uncle has a friend that works at a local transmission shop. I'm going to get with him to make sure I've got everything and have help putting it in.
 

Ford Truck Articles

Top