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so, ive been looking, listening and thinking for a bit. been planning on picking up a zf6 from a 99-03 psd with a electronic shift t/c on it and throwin it into my girl. just wondering if anything is needed to get the tranny into my truck? same bolt pattern right? im not worried about the mounts, i can make that work. zf5 clutch will work huh?
I've heard those are a royal pain to swap into these older trucks. IIRC someone said the tranny tunnel isn't quite big enough and the ZF6 has coolant lines to connect as well. Dont take my word for it though. I swear someone on here or on obn did it and said it wasn't worth the trouble.
well, ive got a 3" body lift so ive got a ton of room under there. i can easily reach my arm around the tranny and the floor board. they do have a cooler, and thats another reason why i like it. im interested in keeping it cool, mostly since ive got 1200 lbs in tires and wheels lol. and im always hauling with her. and ya mech, i wanna grab an extra gear, especially when the 5.38's get in there.
speed-o isnt worth a damn anyways. its about 20 mph off. i was lookin to build a new cluster anyways and use a satellite speedo. anyways, im curious about there needing to be machine work, you remember where or what?
It's definitely not a direct bolt on, and you only really gain an extra gear split. The gear spread in the S5-47 from 96/7 behind the PSD is actually a little better.
Your 5.38's are going to put you back very close to stock with 235/85's and 3.55's, I know with 44's it's pretty much dead on, 46's it'll be like having 33's with stock gears. The taller O/D in the ZF6 isn't going to be necessary.
The ratios for the ZF6 are as follows:
Low gear 5.79
1st gear 3.30
2nd gear 2.10
3rd gear 1.31
4th gear 1.00
overdrive 0.72
Your existing ZF is
1st Gear: 4.14
2nd Gear: 2.37
3rd Gear: 1.42
4th Gear: 1.00
5th Gear: 0.77
The S5-47 95-97 trans is
1st Gear: 5.08
2nd Gear: 2.60
3rd Gear: 1.53
4th Gear: 1.00
5th Gear: 0.77
And the wide ratio version of both is:
1st Gear: 5.72
2nd Gear: 2.94
3rd Gear: 1.61
4th Gear: 1.00
5th Gear: 0.76
It's found in gassers, and supposedly the F450's got a diesel version.
i can get a f450 zf5 for cheap, needs to be rebuilt though. my thought for the zf6 is for the 1st. i haul a ton. lookin for easier take off's. and i do like the wider od. get a little lower rpm's in it, if and when i actually make it without a trailer.
The different O/D is only going to drop you about 130 rpm at 60 mph, nothing to write home about. The gear splits in the 6 are a bit nicer, but, low to 1st is a big jump, mind you it's no different in the wide ratio 5 speed. What would be nice would be to have that 5.79 low with the existing close ratio ZF gear set.
indeed. 130rpm over 16 hours a day and 8 days straight adds up to a lot! over the life of an engine that could be the difference between dying and going an extra 20k miles. and with the zf6 i could potentially take off in 2nd gear unloaded, and still have great grunt when loaded. keep in mind, my truck alone is 10,000 lbs.
There are two ways it has been done.
1 There was a company in oregon that would cut the input and output shaft down, respline them and harden them so you could use the zf5 clutch and tranny case.
2 The top holes dont line up, but it is suppose to be fairly easy to make an adapter for that. Then you have to redrill the flywheel to accept the clutch with the larger input shaft.
ya, from what im getting the 2 top bolts dont line up like you said, but you also have to remove the adapter plate thats bolted to the block. the starter bolts directly to the bellhousing. the flywheel has to be re drilled to fit the zf6 pressure plate. im thinking of going a different rout though.
id take the zf6 friction plate, take it down to my local clutch shop and have them remove the friction material, turn it down to the zf5 size and put the zf5 friction material on it so i can keep my flywheel and pressure plate the way they are.