Who here has put a ZF 5 speed behind a 351/400M? I've done a bunch of searching, but no conclusive results. I have a ZF from a '90 F350 460 4x4, and I'm putting it in a '78 F250 4x4 with a 4 speed. I've heard that you have to space the tranny 1/2 inch from the motor because the flywheel sticks out 1/2 inch farther than the flywheel on a 460. Is this true? I would like to know before I spend the money to make the spacer. Thanks in advance.

 

Here is a thread that goes into some detail a far as a ZF swap goes:

https://www.ford-trucks.com/forums/s...ad.php?t=44122

I have not done such a swap, so that is all the help I can provide.

 

Here a few more:
https://www.ford-trucks.com/forums/s...d.php?t=435162
https://www.ford-trucks.com/user_gal...&albumid=11298
https://www.ford-trucks.com/user_gal...4&albumid=6971

 

1975-looks like all those links are for putting the ZF behind the 460, not the 351m/400.

I too am really serious about putting a ZF on my bronco (351m/400), unfortunately the only good info is what firstonraceday linked, and although it doesnt sound too hard I really dont know much about trannys and wouldnt be able to do it myself without more detailed specs. So far I havent found any place localy that will do a custom tranny swap that needs fabrication. But if I did find a shop / person that would do it I would be sporting a 5speed in no time. So if you find any more info then be sure to post it!

 

I have seen some on the boards contemplating a swap such as this mention going to hydraulic clutch. Seems as though this could alleviate some of the linkage fabrication, HOWEVER, I am no fan of hydraulic clutches.

I know from dealing with the one on the '93 I had that some things needed for a hydraulic setup would be:

Clutch pedal assembly (with provision for clutch master cylinder pushrod)

Clutch master cylinder w/pushrod

Lines

And possibly the firewall bracing kit which Ford made for retrofitting into early generation trucks with hydraulic clutches.

This is just a possibility to consider. It might or might not help with the swap. As I said in the earlier post, I haven't done one of these swaps and am currently not considering one as I fillied the '77 with gas this morning and hand calculated the mileage at 16 mpg - 60% hwy and 40% city. That mileage hasn't been consistent but the rebuilt engine only has about 4,000 miles on it.

 

Thanks for the replies, sorry I haven't been on here for a while. I think that I figured out how I am going to do it. If anyone else has any suggestions, they would be greatly appreciated. Thanks again guys

 

so the ZF tranny has a different bolt pattern that won't allow it to be bolted up to any bell? Spacers are no problem for me, I can fab things like that at work. I also was concidering an OD manual for my 78 with a 390 in it so I could go back to 4:11 gears and be able to run down the highway with it at a reasonable speed...Neil

 

Neil... The ZF has an integral bell housing and isnt removable.

As far as milleage goes I think the OD would defanetly help, especially on the highway. I hope to eventually take my bronco on 2-3hr drives occasionally as its that far to were the family is and all the farms and places I hunt. Even if you get good milleage it doesnt matter as the OD should increase it some. And the way I look at it is if it increases your milleage it will actually pay for itself. Would you like to have a free upgrade? Sure it may take a while depending on how much is spent and the amount it raises the milleage by.

I know a lot of folks here love their manual clutches but I could not imagine driving one dialy in Columbus Ohio. Thats were I currently reside & work. I have owned 4 vehicles with hyd clutches and have yet to have a problem with any (knock on wood). I have driven a late 70's f250 and a chevy that had manuals, also my dads old stang. I was not impressed. I cant see any advantage they would have other than maybe being more durable? The clutch was so hard to press down in the chevy that I pushed down hard enough my muddy shoe slipped off the pedal and put a hole in the floor board! I suppose if you grew up with manual clutches it would be different. My first vehicle I learned to drive with was my dads '93 f-150 5speed with the I6.

 

Here's another option https://www.ford-trucks.com/article/...rd_Bronco.html

 

I swapped a M50D manual 5 speed on my 1978 F150 2wd truck with 302 cid and the hydraulic clutch setup. I setup the truck for gas mileage improvements and some load hualing. I have a F250 4x4 high boy for the heavier load hauling or towing.

 

1975... I forgot about that option. I read that article a few years ago I beleive. Unfortunatly thats more than I want to spend. $3500 might even be conservative considering the extras like the stainless steel braided dipstick and shipping costs, etc. I wouldnt doubt if it would cost a bit more. It does sound like a very good swap though, but if you actually want a stick shift than the aod isnt an option - and also with the aod you dont get the granny gear the ZF has. And it appears there is almost as much fab work involved either way. Thanks for the link though!

 

ZF is a better transmission for hauling "nothing beats a granny gear"

 

Just an update. I pulled out the four speed and started the swap process. I had to fold up the pinch weld on the firewall and cut a couple of ears off of the tranny, but other than that it fits really well. The hole for the shifter had to be lengthened by about 3 inched toward the back. The tranny mount off of the four speed bolted right up to the ZF. The hole in the tranny crossmember was in the right spot side to side, but the whole thing moved about an inch and a half to the rear. Just have to redrill some holes and it should work great. My clutch disk will be here on Monday or Tuesday, so I should be able to take care of that next week. Thanks for the replies. I'll update this when I work on it more.

 

Definately keep us updated. Heck, if you were local I'd probably give you a hand just to see everthing you've done. Anyways, what are you doing with the clutch, keeping it manual or using the hyd from the zf? And what are you using for a t-case? A married np205 I assume?

 

I'm using the married 205 for the t-case, and I'm keeping the clutch mechanical. This was an earlier ZF so it had the slave cylinder mounted to the side of the tranny that pushed on the clutch fork, so making it totally mechanical was easy. I just had to cut off the slave cylinder mounting bracket. My clutch disc will hopefully be here on tomorrow. I've taken a bunch of pictures, I just need to take the time to load them on to the computer, I will put them in my gallery though. Thanks again for all of the replies. I will keep you posted.