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Discussion Starter · #1 ·
Greetings,

I hope some of you have been through this process before and can shed some light for me. I'll figure it out on my own, but it will take 5 times longer than if I get feedback from someone who has already done it.

I've got a 93 Grumman-Olsen Step van with the 4BT and a Ford 4-speed (T-19) I think. It also has the park brake attached to the tail of the trans. Because of the gearing, it won't go any faster than 60mph on the highway, a real road-block.

I've purchased a ZF5 from a 4.9 5.0 5.8 gas engine vehicle with 4X4 on the advice of a fellow who parts these vans out. It appears the bell housing bolt pattern is correct. However, the ZF has the internal slave cylinder. Any advice on a hose that will reach my master?

Also, I purchased the rear park brake that bolts up right where the transfer case would. I've test fitted it and it fits perfectly. My only problem is that there is no speedometer cable drive. There is a depression in the casting for it, and it may be something I can pop out. But will there even be a drive gear on the output shaft to drive the speedo gear?

And from other posts to this site, it appears I will have to get a different clutch, flywheel and pilot bushing/bearing.

Any advice would be greatly appreciated!

Mike
 

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usually on a 4x4 transmission the speedo gear is on the transfer case--that way when you go to 4 low the speedo works right-----if that depression is a freeze plug looking thing that may be the spot---otherwise GPS speedo always works----a picture of the spot may help....also the hose that fit the gas unit may well be long enough to fit the van---a place like tubesnhoses can make any length you need....
 

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Discussion Starter · #3 ·
Thanks for the response. Yeah, I'm pretty sure this is where the speedometer driven gear sleeve would go. I'm trying to get the brake shaft nut off so I can remove the bearing and see if there is actually a drive gear already on the shaft. I found a few blow-apart diagrams on line that show a gear there.
 

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Discussion Starter · #5 ·
Thanks for the response. No, both the transmission and the parking brake assembly are ZF components. However, the parking brake was most likely from a later year when, as you mentioned, the rear axle speed sensor was used for vehicle speed. I still think I can make it work if I remove the plug and drill a hole for the speedometer gear sleeve. I was hoping somebody on this site has actually done this. If not, I guess I'll be the first!
 

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Only the ZF 2wd S5-42 had the provision for a speedometer cable. It attached on the side of the rear housing. I don't believe the S5-47 even had it since the speedometers were electronic by then and read off the rear axle. The 4wd trucks all read off the transfer case or rear axle in later models. The F Super Duty (F450) used the parking brake assembly. I honestly don't remember where those trucks got their speedo reading. I suspect the rear axle, but that's just a guess. Be sure to keep check on the oil in that brake unit. I believe you're the first with this swap.
 

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Discussion Starter · #8 ·
Okay, here we go. I pulled the BW 4-speed out of the vehicle today. The ZF5 is about 8 inches longer, so I will need to do the following: relocate cross member, modify driveshaft, come up with a longer hydraulic clutch line, and maybe a longer cable for my park brake. There is some slack in the brake cable, it might be usable as is.
The good news is that the input shaft appears to be the same, as well as the bell housing. Hopefully I won't have to change any clutch components. I've included a couple of pictures so you can see the difference.
I need to find a 65mm socket so I can remove the bearing from the park brake assembly. I need to see if there is already a gear there. I did find a listing for one from a transmission parts place, so if it doesn't have a gear, I can get one. I still don't know how hard that "plug" is to remove for the driven gear. I'll find out soon and post it as well. DSC03384.jpg DSC03385.jpg DSC03386.jpg
 

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Discussion Starter · #10 ·
Here's a link to a full service guide on that parking brake from Auto Zone. Doesn't mention anything about removing the plug though. Possibly they have that socket in their loaner tools.
Thanks for the link. Yes, I've seen this before, and I'll be removing the outer bearing too see if the drive gear is present as in figure 11. I also think I can push the plug out from the inside. If not, I'll have to drill it out to accommodate a speedometer sleeve and driven gear.
 

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Discussion Starter · #11 ·
Well, the good news is that there are multiple cross-member mounting holes in the frame, both top and bottom. I relocated my cross-member to the next set of holes back, which is approx. 3 3/4 inches further back. The difference between the BW and the ZF trans mount locations was 3 1/2 inches. The holes in the cross-member for the trans mount are elongated, so the 1/4 inch difference should not be a problem.

P.S. Does anybody want the transfer case link, bracket and bolt I removed from the ZF? (See Picture) DSC03388.jpg DSC03389.jpg
 

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Discussion Starter · #12 ·
Well, I successfully installed the ZF5 today. I knew the shifter was further back than with the BW, but it was so far back, I had to remove a body cross member and floor plate. Both can be modified, not that big a deal. I'm still waiting on a socket I ordered so I can get the park brake assembly apart and attempt to hook up a speedometer. ZF5.jpg
 

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Well, one down and one to go. On your park brake unit, I suspect the one you have is from the later 90's model F Super Duty which had the electronic speedometer that read off the rear axle. Hence, no port for the speedo. If you had one from the late 80's to early 90's it would be there.
 

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Discussion Starter · #14 ·
Yes, I believe you are correct. I purchased this brake unit for $150, so I really didn't care if I had to modify it. If I can't, I'm sure I can rig an electronic speedometer instead. These stupid brake units go for $750 for even a rebuilt one!
 

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Where did you buy the brake unit and where did you see them for $750? I have one I'd be happy if I could get $100 for it...
 

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Discussion Starter · #16 ·
Where did you buy the brake unit and where did you see them for $750? I have one I'd be happy if I could get $100 for it...
I happened to find an ad on Craigslist for $150. The lever was slightly bent, and the unit did not have an opening for a speedometer, but it was still a good find. I see the $750 units on eBay all the time.
 

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Discussion Starter · #17 ·
Almost there......

Well, after hunting in vein for a hydraulic hose that was long enough to reach my slave cylinder that also had the correct fitting, I gave up looking for a vendor made hose. The one for a F series truck was too short, since the firewall of a pick up is closer to the bell housing than on this van. I finally had to have a brake specialty shop make a hose up for me, to a tune of $80. I only wish I had done this first, I could have saved a lot of time and money.....live and learn. (Anybody need a clutch hose for a 90's F series with an internal slave cylinder? I have a new one that is only slightly dirty!! Cheap!!) Once I got the hose in and the system bled, I took her for a spin. The shifter will have to be modified, it's hard to reach as is. But other than that, it drove, shifted and clutched very nicely.
I now have to rig up and electronic speedometer since there was no cable drive with this set up. I will also have to modify my floor boards....stay tuned.
 

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If you could get one of the speedometers that operates off GPS that would take care of you. Those are becoming very common now. Don't have to worry about cables, tire size, or gear ratios.
 

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anything unusual regarding the driveshaft modification. i am planning this swap, was wondering if anyone has modified the rear axle ratio on these stepvans
i plan to use is it on the highway and would like to get the rpms down while at speeds of fifty five to sixty.

also, i have the mt 35 and wondered if swapping in a 6bt has been tried. the truck's suspension is over built and could handle the marginal weight of the six bt, everything should mount up, with room to give at the front of the engine bay for the longer six cyl eng. grummen used to make a full size van with a 6bt and manual tranny though i have not seen one for years nowl
 

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Use the tallest ratios available, probably 3.54. If you have both a 4bt and a 6bt available I would personally use the 6 myself.
 
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