zf-6 speed's
- Thread starter bigblue85
- Start date
I thought on a transmission thread about the E4OD and 4R100 there were 2 different bold pattern 4R100's..... Let me go look.....
OK, Went for a look and this is the thead that I found...
http://www.oilburners.net/forums/showthread.php?t=51924
OK, Went for a look and this is the thead that I found...
http://www.oilburners.net/forums/showthread.php?t=51924
trapper
Boom Boom
Ok, I am still getting occasional requests for info on how to do this swap, so I'll make a post with all the info I can remember on how to do it. It's been almost 2 years since I did it, so please excuse anything I forget to mention.
I now have about 20,000 miles on the truck with the conversion, and could not be happier. My only complaint in that time was with the ceramic puck style clutch disk I used. I have since replaced it with a conventional LUK disk and love it! There will be more on this to follow.
First of all, you have to remove the approximately 1" thick adapter plate the IDI's use in order to get the clutch and flywheel spacing correct. In other words, the bellhousing on the ZF6 is deeper and the input shaft is shorter, so the spacer has to go. The 7.3 powerstrokes have a different bellhousing bolt pattern cast into the block compared to the IDI. The good news is the 2 dowel pins, and 4 lower bolts do match up. The upper 2 bolts are the only difference. I made a stepped adapter to go from the upper 2 bolts on the IDI block to the upper 2 bolts on the ZF6. It was 2 pieces of 1/2" x 2" flat steel bar overlapped and welded together, making sure both bars were parallel after welding. The lower bar bolts to the upper holes in the block, and the upper bar sits behind it and has the upper 2 holes tapped for the tranny bolts. That makes the front face of the upper part of the adapter flush with the rest of the bellhousing in the block. I bought the stock tranny dust plate for a '99 and had to cut a little clearance into it for the adapter.
The next big hurdle is the clutch. The ZF6 has a 1.375" input shaft, and the smallest disk you can find with that spline is going to be 13" diameter. A 13" disk will not fit under any pressure plate that fits an IDI flywheel. My first way around this was to use a custom made 12.25" disk with the 1.375" spline and 4 ceramic pucks per side. This disk turned out to be miserable! The more you tried to slip it, the harder it grabbed sending the truck into convulsions. Backing up to a trailer was virtually impossible. So, I recently went a different route.
I had already used a LUK solid flywheel, so I pulled it back out and redrilled it for a LUK 13" PSD pressure plate. I now have the LUK pressure plate and disk for a '99 PSD and it works great. It reduced the pedal effort, virtually eliminated the gear rollover noise, and is very smooth. This is definitely the way to go. Oh, and you can't use a LUK flywheel for a PSD because they have a different bolt pattern on the crankshaft.
The clutch hydraulics weren't too bad, but not a simple bolt together deal, either. I used the correct master cylinder for my year truck. I used a slave cylinder for a '99 ZF6. The fork, pivot, and throwout bearing were all for a ZF6. The only real problem was trying to come up with a clutch hose that would work. I ended up making adapters that fit into the clutch and slave with a -3 AN on the other end. I then made a stainless steel braided hose to connect them. Bleeding was the typical pain, but it has worked great ever since.
The shifter ended up in exactly the same spot as a ZF5, so the tranny tunnel cover for a manual and boot all bolted up fine. I made my own cross member for the back of the tranny by heavily modifying the one that was in my truck with the E4OD. You might be able to bolt in a cross member from a '99 ZF6 - I'm not sure - was too cheap to buy one.
Of course you'll have to visit a driveshaft shop and get yours modified or a new one made. I also went to a '99 E350 disc brake rear axle at the same time, and had an all new driveshaft built to fit.
The ZF6 does not have a speedo drive gear. This is where a '92 up truck has the advantage. I used a speedo from the '92 up truck and made it fit inside my cluster with some slight customization. The '92 up speedo is all electronic, and I was able to drive it from the sensor on the rear axle.
The 7.3 IDI starter bolts directly into the bellhousing of the ZF6 and works fine. The bellhousing lower cover for the '99 bolted right up.
Oh, I did have to bend the floor of the truck up just a little bit for clearance, but it's under the seat and totally unnoticable.
I think that about covers it... If I remember anything else I'll reply to this post. If anyone wants a flywheel redrilled I could probably take care of that part of the conversion for them.
I now have about 20,000 miles on the truck with the conversion, and could not be happier. My only complaint in that time was with the ceramic puck style clutch disk I used. I have since replaced it with a conventional LUK disk and love it! There will be more on this to follow.
First of all, you have to remove the approximately 1" thick adapter plate the IDI's use in order to get the clutch and flywheel spacing correct. In other words, the bellhousing on the ZF6 is deeper and the input shaft is shorter, so the spacer has to go. The 7.3 powerstrokes have a different bellhousing bolt pattern cast into the block compared to the IDI. The good news is the 2 dowel pins, and 4 lower bolts do match up. The upper 2 bolts are the only difference. I made a stepped adapter to go from the upper 2 bolts on the IDI block to the upper 2 bolts on the ZF6. It was 2 pieces of 1/2" x 2" flat steel bar overlapped and welded together, making sure both bars were parallel after welding. The lower bar bolts to the upper holes in the block, and the upper bar sits behind it and has the upper 2 holes tapped for the tranny bolts. That makes the front face of the upper part of the adapter flush with the rest of the bellhousing in the block. I bought the stock tranny dust plate for a '99 and had to cut a little clearance into it for the adapter.
The next big hurdle is the clutch. The ZF6 has a 1.375" input shaft, and the smallest disk you can find with that spline is going to be 13" diameter. A 13" disk will not fit under any pressure plate that fits an IDI flywheel. My first way around this was to use a custom made 12.25" disk with the 1.375" spline and 4 ceramic pucks per side. This disk turned out to be miserable! The more you tried to slip it, the harder it grabbed sending the truck into convulsions. Backing up to a trailer was virtually impossible. So, I recently went a different route.
I had already used a LUK solid flywheel, so I pulled it back out and redrilled it for a LUK 13" PSD pressure plate. I now have the LUK pressure plate and disk for a '99 PSD and it works great. It reduced the pedal effort, virtually eliminated the gear rollover noise, and is very smooth. This is definitely the way to go. Oh, and you can't use a LUK flywheel for a PSD because they have a different bolt pattern on the crankshaft.
The clutch hydraulics weren't too bad, but not a simple bolt together deal, either. I used the correct master cylinder for my year truck. I used a slave cylinder for a '99 ZF6. The fork, pivot, and throwout bearing were all for a ZF6. The only real problem was trying to come up with a clutch hose that would work. I ended up making adapters that fit into the clutch and slave with a -3 AN on the other end. I then made a stainless steel braided hose to connect them. Bleeding was the typical pain, but it has worked great ever since.
The shifter ended up in exactly the same spot as a ZF5, so the tranny tunnel cover for a manual and boot all bolted up fine. I made my own cross member for the back of the tranny by heavily modifying the one that was in my truck with the E4OD. You might be able to bolt in a cross member from a '99 ZF6 - I'm not sure - was too cheap to buy one.
Of course you'll have to visit a driveshaft shop and get yours modified or a new one made. I also went to a '99 E350 disc brake rear axle at the same time, and had an all new driveshaft built to fit.
The ZF6 does not have a speedo drive gear. This is where a '92 up truck has the advantage. I used a speedo from the '92 up truck and made it fit inside my cluster with some slight customization. The '92 up speedo is all electronic, and I was able to drive it from the sensor on the rear axle.
The 7.3 IDI starter bolts directly into the bellhousing of the ZF6 and works fine. The bellhousing lower cover for the '99 bolted right up.
Oh, I did have to bend the floor of the truck up just a little bit for clearance, but it's under the seat and totally unnoticable.
I think that about covers it... If I remember anything else I'll reply to this post. If anyone wants a flywheel redrilled I could probably take care of that part of the conversion for them.
typ4
Full Access Member
That needs to be in the tech section, great info.
trapper
Boom Boom
go for it
Diesel_brad
Dunce
I have a ZF5 and a ZF6 in the garage(out of trucks). IF i have time I will get some measurement, But i am pretty positive, they are the same bolt pattern
You have to swap the transfer case for the later type if you have 4x4 and swap the zf6 in correct? I believe I am correct in saying this is the first time ever that Ford changed the shaft diameter and possible the bolt pattern on the input of the transfer case, so none of the old ones will work. And of course this is part of the speedo connecting problem, since the later transfer case doesn't have a spot for one.
Diesel_brad
Dunce
Yes. You HAVE TO use a SD transfer case. AND it has to have come from a ZF6 trans. the shaft diameter is the same, but the spline count is different between a auto and a ZF6
riotwarrior
Full Access Member
Just got a line on a 6sp, with tcase for my truck to replace this worn 3rd gear grinding ZF 5sp.
I'm thinking if the deal is cheap enough for me, I'll be all over this like nobody's buisness. It appears I'll need a LUCK single mass flywheel setup for my truck so now gotta start looking for one cheap for redrill!
Hmmm....
Just waiting on Wife's uncle to get me a price on the unit he's got sitting in his yard in a frame still! Ya...COMPLETE even has the oil cooler!
Makes me hope like hell it's going to be dirt cheap!
I'm thinking if the deal is cheap enough for me, I'll be all over this like nobody's buisness. It appears I'll need a LUCK single mass flywheel setup for my truck so now gotta start looking for one cheap for redrill!
Hmmm....
Just waiting on Wife's uncle to get me a price on the unit he's got sitting in his yard in a frame still! Ya...COMPLETE even has the oil cooler!
Makes me hope like hell it's going to be dirt cheap!
fordf350man
Full Access Member
that sounds great **** the 6 speed swap, that would be great for towing, there is a few YOU-PULL salvage yards around here, any transmission for 70 bucks, im going to see what there prices are, might do this this summer
79jasper
Chickenhawk
May be kickin a dead horse but I can confirm that a zf-5 from an idi will swap directly into an obs psd and vise versa. Just did it. The clutch master cylinder mounts a lil different, but nothing a drill can't take care of til I can buy a new one.
Double-S-Diesel
parts seller
dect swap, the slave is different on a idi, bu they will interchange,
had a 88 zfiidi in my 96 psd
hesutton
The Anti-Anderson
I don't know.... That's a lot of work to gain a granny gear.
Heath
Heath
riotwarrior
Full Access Member
Not JUST a granny gear,
I've driven two tow trucks one ZF5 sp oe ZF6 sp basically identical other than body OBS/SD and I gotta tell ya that 6sp is sweet to drive, better gear spacing, lower reverse, I just like it.
The only way this will happen, is that I get the 6sp and tcase so forth at a ridiculous price, otherwise I'll stick with finding a replacement 5sp cheap!
It is just a option that has come up for me. Super Wifey's uncle has a chassis with the 6sp sitting there no engine stripped down no box no cab etc out o the farm. Might get a smokin deal on it so then it's worth it!
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