Relates to all big sixes
Making a post for discussion and questions that may come up. Hoping to have this post for me and anyone who wants to do a project like this.

Recently started a project with my son. We are working on restoring my dads 1988 f250. It has been setting in a fence row for 15 plus years so we have our work cut out for us. It has a 460 in it with a 5 speed. After many conversations and trying to figure out what the plan was we decided to swap the 460 for a 300. Reason being fuel and ease of maintenance.

Anyway I have been researching and racking my brain on all the things we will have to do to get this swap done right. My plan is to do things the right way the first time instead of just trying to get by. Because of this we are pulling a 300 out of a parts truck that we recently picked up. The motor seems to run great. Its the rest of the parts truck that was in need of work. Once pulled we will be taking it to a local machinist to be cleaned, checked, and bored if needed. Any ideas for what we can have done or should have done while there? My goal is 200 horse power and 300 torque. Keeping in mind it will be an everyday driver for a 16 year old.

While the 300 is at the machinist we will be pulling the 460, transmission, and transfer case out of the project truck. We will then take the truck's transmissions and transfer case to our local transmission mechanic and have them gone through to see what one is worth keeping and having transfer case confirmed it is good to go. I know the 460 transmission won't hook up to the 300. The plan is to see what internal parts are good in the 460's transmission and swapping them into the 300's transmission. I am not a transmission guy just going off what guy said. He is well respected in my area so I trust what he says. Again any ideas suggestions? While it is there anything that could be done to keep them going longer than original?

We will be waiting on the engine and transmission for awhile so in that time the plan is to strip interior and completely redo it. I seen several post on this site and others were guys replaced bench seats with bucket seats. I am hoping to do the same while adding a center console. The part I am struggling with is at what point should this truck go to a body shop? It would seem that at this point it would be ideal? Am I wrong? There are many other things that we will be doing to this truck just wondering when most logical time to take it to body shop would be?

Other ideas / upgrades to be done
Replacing both tanks. bigger in rear for sure. While verifying and replacing as needed fuel lines
upgrading to disc breaks all around while checking break lines and replacing as needed
suspension upgrades as needed
clean up engine bay as best we can. Want to make it clean looking (ideas?)
Electronic upgrade. Most likely ECU

There are a lot of ideas that we have that we want to do and some that probably shouldn't be done or are a waste of time. I would appreciate any and all advice with this project. I am not a mechanic as you can probably tell from my post. The biggest thing about this project is it allows my son and I to work together and bring back an old truck that my dad taught me how to drive on.

Thank you guys look forward to hearing from everyone!
 

OldTrusty80

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One suggestion from my 460-300 swap, make sure you keep the engine frame stands from the donor truck, the right ones weren't too easy to find for me. Gary's Garagemahal website has a good reference section for motor mounts and frame stands for different years and engines.
 

BigBlue94

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Ditto on not parting the 460 ZF5 transmission. Thats a $500 trans on CL all day long. If the 300 was in a half ton, the 5 speed would be a totally different model.
 

BigBlue94

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It’s from a 1989 f250
As long as its all original, then both would be the ZF S5-42.

The ZF5 is a very sought after trans for nearly any ford from the 20th century. The bellhousings are integral, so there arr SBF (and 300), BBF, and International Diesel versions. All are desired
 

sdiesel

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ill have 2 available very soon in the 300 pattern. i need but one. input shaft is generally bonkers on these a full rebuild should be expected by any zf user
 
I have the 300 out of parts truck. Went to put it on engine stand and apparently I bought a junk one. Won’t hold the weight. Have to have cherry picker and engine stand together to hold it.
Note to self: don’t try to save money on engine stand. Get the right one first time.
 

F-250 Restorer

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I recently went through the ZF5 rebuild and I'd be happy to share what I learned. It could help you and save you some money too. The problem with the zf5 is that the ZF factory in Germany has stopped making replacement parts. Getting non-Chinese bearings is VERY difficult. Chinese bearings will last about a year, maybe. Even some of the big name trans shops are selling them. The only good bearings are made by Koyo, a Japanese firm. Here is a link to find them. https://www.transmissionpartsdistributors.com/search.php?search_query=zf5

Also, don't use the brass syncros. Get the steel ones.

Also, be aware. The zf is ... loud. Half the time I love it, and half the time I hate it. It rumbles loud enough at idle to be very irritating. The shifts are long and extremely slow, kind of like having to double clutch every shift. For the cost of having a zf rebuilt, there are other trans out there to consider. Good luck.
 

sdiesel

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i'm unaware of steel synchros, unless you mean the fiber style . the big problem with brass is incompatible fluids, why say you the brass are not acceptable?
zf is loud especially if front bearing is worn or out of spec or shaft preload is messy.
ive had smooth zf and one currently that rumbles like rocks in a river torrent.
the slow shift is fixed by midwest trans and their short shifter.
koyo bearings....top shelf stuff.
buy motorcraft slave cylinder.
im going to look into those bearings. i cannot imagine any of those sizes are proprietery. but maybe

there are any number of shafts available. i just bought a new input shaft for 130. hope its a state side shaft
 

Sevensecondsuv

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I rebuilt a 460 ZF last summer. Finding a kit with koyo bearings was easy and not too much $$$. It did have the iron syncros, which was the factory spec for these transmissions. I also replaced the input due to the pilot surface was thrashed on the old one.

From what I can tell, all parts for these transmissions are now coming from Midwest/Zumbrota/USA Standard Gear or various other names for the what seems to be the same entity in Zumbrota, MN. In any case the parts are good quality and reasonably priced.

Mine has worked out good since the rebuild. It's about as quiet as I've ever heard from a ZF (I've had about a half dozen now), but I do agree they're not the quiet like an M5OD is. While the shifting on my rebuilt one is as tight and smooth as it should be, the ZF design makes for not great shift quality. I describe the shif feel as "numb and notchy". It's decidedly worse feeling than an M5OD and I even prefer the feel of the old T18 or NP435. That said, the ZF is plenty strong, has excellent ratios for a gas rig, has overdrive, and fits our Ford engines. Just don't expect to drive it like a sports car.
 

sixtseventwo4d

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I have the 300 out of parts truck. Went to put it on engine stand and apparently I bought a junk one. Won’t hold the weight. Have to have cherry picker and engine stand together to hold it.
Note to self: don’t try to save money on engine stand. Get the right one first time.
Many stands that claim a weight rating that simply won't do because of the block length. A 4 point stand is needed and you still may want to extend the legs.
 
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BigBlue94

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Ive never had a noisy ZF, but ive only had one, behind a 95 F250 460. I also never minded the shifter, though I also drive an NP435 with 400k miles on it. Its worn out. I still would rather have a ZF6 before either for a street driven truck.

I bought a ZF5 with a truck wrapped around it. ZF5 was recently rebuilt with a couple new gears. But they used gear oil instead of ATF. I tore it down to the main assemblies and gave it all a 3 day soak in ATF while moving parts around. Cleaned all the oil out and went back together smooth.
 

InlineDave87

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Oh man them ZF6 transmissions were sweet especially behind that 7.3 diesel... when i had to swap shop truck and drive an 01 7.3 ZF6, being as young as i am my boss turn back and asked me, do you even know how to drive standard... me... “why do you need me to show you how?”... my pops didnt raise no fool
 

BigBlue94

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Oh man them ZF6 transmissions were sweet especially behind that 7.3 diesel... when i had to swap shop truck and drive an 01 7.3 ZF6, being as young as i am my boss turn back and asked me, do you even know how to drive standard... me... “why do you need me to show you how?”... my pops didnt raise no fool
Im driving an 08 RCLB F350 4x4 with a 5.4 in front of the ZF6. I can shift it with my elbow planted, not moving. Just a flip of the wrist. Ive driven 7 different manual trans, 6 of them in 4x4s and the ZF6 is my favorite. The NP435 behind my 300 is near indestructible, otherwise i would've swapped one of the 4 ZF5s i have on the shelf in it.
 

bubba22349

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Never drove a ZF5 yet, loved my NP435 in my 65 F350 truck but it sure could of used a 5th OD. Black in then I was trying to get ahold of one of the Clark 5 speeds to use in it.
 
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