Looking for some guidance

Hello again great oil burners of the internet! I have a bricknose F450 2wd 7.3L ZF5 that I am currently working on. It’s a service truck for a local hay operation here in amador county. My client has lost reverse in his transmission and needs it repaired.

Now I recently pulled a ZF5 out of my dads old bricknose feed truck but that had a 351 Gas engine in it.

My question is, are the gears inside my 351 ZF5 the same as a diesel ZF5?

If so I believe I can just swap over the input shaft, bell housing and tail end of the diesel ZF5 over to my 351 ZF5 and stick it right back in the truck. I have a feeling the gears are different however....

can swap cases like that, there is some shimming involved, gear ratios different also.

If the truck uses pto, the gear most likely WONT match. There are several different ones for the zf5.

Check the stickies

Update today: transmission has been removed and it would appear someone might have bent the fork for reverse. The oil has plenty of metal in it as well. Had a bad clutch for a while and had a careless driver.

Now everyone and their mother has been telling me a 351 zf5 has a smaller input shaft, but it would appear they are the same size. Not sure how this is possible. The clutch disk fits snug on both shafts. The bell housing bolt holes do need to be drilled out to fit, I couldn’t compare the info plates because the trans in this bricknose has been rebuilt.(company removed it) going to slap it all together, change the oil and pray to the ford gods it all works out. If anyone has any input before I throw it in I would appreciate it. Thank you in advance.

The ford ZF info plate is the one off the 351. The one that was torn off with the rebuilt tab is the 7.3L ZF

The trans in the first pic with the original tag, are you sure that’s not a diesel trans?

It came out of my dads bricknose gas 351 F250. Maybe someone put a different trans in it when I was a kid. I’m not sure. But if I had to drill out the bell housing holes it had to be a gas trans right?

Zf5-s42 is the diesel model, if that tag goes with that case it should all line up

Update: we got the treats jerry rigged up on two jacks and got it so close, after 30 min of sailer swearing we discovered the doul holes don’t line up.....going to drill them and try again. We are persistent and will conquer this IDI. No matter what

Hard to see, but the dowel holes don’t line up.

I have a complete 302, bellhousing, new flywheel & clutch, and a 2WD ZF-5, all bolted up. Was going to put it in my automatic F-150 with a bad engine, but bought my 93 F-250 IDI instead. Will sell just the trans if you're interested... PM me

Too bad that I decided to keep my 81 F150 as an automatic. I'd be interested in it otherwise.

So I Have come to two conclusions to this problem I’m currently having.

First one is this, the 351 ZF5 will match up with the top two bell housing bolts. The two below that are about 1/2 and inch off or so it looks like. And the other two below that are even further apart. There is enough case left to drill that I could possibly extend the middle bell housing bolt holes on both sides to make up the 1/2 inch. But in the end I would have to have no dowels, and would only be holding up the trans with 4 out of 6 bolts to the engine. Not ideal. But this would take the least effort.

Second method is take the guts out of my 351 ZF5 and swap the diesel case on it, that way I got all 6 bell housing bolts. I’m not too experienced with these transmissions yet so I will have an old mechanic with me to help. Hopefully swapping the cases goes smoothly. if anyone on here has any input or wise words on this problem I’m having I would very much appreciate it. This website is truly gods gift to ford owners, thanks again.

Are you sure that’s not a big block ford gasser trans?? I thought the sbf was a good bit smaller pattern. The swap of bbf to diesel is well documented. Holes need to be modified but the top holes and I think the dowel pins line up.

Small block



Big block

Update: ended up swapping the cases over. Took the 351 ZF5 guts and stuck them into the 7.3 ZF5 case. Everything went smooth upon installation and she backed herself right out of her grave. So far everything is operating correctly and the customer is glad he didn’t have to pay a shop to do it. Next to fix on her is the head gaskets and the crane she has. Will post future threads when repairs are being done. Thanks again oil burners!