Friends,
The Synchros in 3rd to 4th in my T19 4 speed 84 idi 4x4 is causing me to double clutch and wait before finding 4th. I'm feeling the best solution is a Zf5 swap. I know on the surface the 95-97 Zf5 model was more robust. Does it make much difference to wait for one or just find an available zf5 and go? I'm grabbing it from a picknpull. What else should I grab? Drive shafts? Transfer case? I know the support beam that goes with the zf5 needs to used as it dips lower by a bit and the drive shaft needs clearance.

Also I have a gv overdrive on the T19. It isn't engaging. But my plan is to fix it and use it with the zf5.

Your expertise is appreciated.

 

I'm in the middle of swapping from a 4x2 ZF5 to a 4x4 ZF5. I went with the S47 version because of the additional torque capacity (I'm going with a mild build on a 7.3 IDI turbo, hoping for 250/550 at the wheels). If you're going to keep a stock 6.9 I'd just grab what I could find. However, there's an issue for most of the 4x4 transmissions - the dreaded cracked extension housing. I did a few videos on this on my YT channel; links below.

As for what to grab, you'll need the crossmember, and I'm assuming the driveshafts are different, too. Having said that, you can buy the front driveshaft new, or at least I can find one for my truck. You may be able to shorten the front portion of your rear shaft, too.

I'd also plan to refresh the ZF5 unless you pull it from a truck that you've had a chance to drive; they're big heavy suckers and you'd hate to have to pull it again once it's been installed.

As for the transfer case, what do you have now? 1356? That's what I'm going to run in my truck.




Hope this is helpful.

Scott

 

Thanks Scott. I am upgrading with a turbo banks sidewinder as well (already purchased, just waiting for some warmer weather to install). Still debating if I should swap the Manifold bolts to studs. So I think going with s47 would be preferred. What would you recommend refreshing in the transmission before installing?

I'll check out your videos!

Chad

 

Chad - if you're installing a turbo, head studs are a good idea, especially on a 6.9.

On the ZF-5, I'd plan to replace all the synchros, at a bare minimum. For my build, I also replaced all the bearings and a few of the gears that had some wear.

The S47 is preferred, but if it's a stock build with a turbo, you should be fine with an S42, especially if you have problems sourcing an S47. Also, you need a diesel version of the ZF5; they don't have a bellhousing, so the cases themselves have different bolt patterns for each engine family (diesel, small block, 460).

Scott

 

I don`t have any info on what you are asking, but do you want to sell the GV adapter off your T-19?
I pretty sure it won`t fit on the ZF.
I have a GV I got off a 89 at PNP, that had a C6 Adapter.

You can private msg me through the Forum.

Charlie

 

I don’t think you’ll go wrong with either. That said, which ever one pops up first that’s in the best condition/lower miles is the one to get. Getting a trans from a highway cruiser is gonna have less abuse than say a plow truck that goes between 1,2 and R all week long.

The 47 is stronger, but I don’t think the 42 is weak. Unless it’s a wild build a 42 should handle it. Having driven both, the 47 has a much shorter throw then the 42. There’s short throw kits available, so no worries there.

Have a good look over the one your going to buy and make sure there’s no hairline cracks or anything anywhere on it, which I think you already know. Depending on what gears you have in the rear, you might not need your OD unit with a zf5

 

If you have a 4x4, the 5-speed is within less than 1/8" of being exactly the same length as the 4-speed and has a 31-spline mainshaft (so you can reuse your existing t-case) so what you will need from the donor truck is:
-ZF transmission
-transmission tunnel cover
-5-speed crossmember
Additionally, the 5-speed has a larger input shaft, so you will need a different clutch. The stock clutch for the 5-speed has a solid hub for the stock dual-mass flywheel, so get an aftermarket clutch for a solid flywheel and have your flywheel drilled and tapped as needed; alternately, you could buy the flywheel and clutch as a kit.
I'm not sure if the hydraulic slave cylinder is the same, but I bought a complete assembly (master cylinder/line/slave cylinder) for my 94 for like $80, metal body on both, pre-assembled with no bleeding required.
​​Having driven both, the shorter 1st and reverse in the S5-47 are nicer to have for trailers. Not a huge difference, but nice nonetheless. Unless you plan to make big power, either will work just fine.
Follow the advice others have given, and enjoy the better fuel economy!

 

I went with Luk solid flywheel/clutch/pressure plate kit. About $350 or so, but they're not packaged great so you may end up with damaged parts. Mine came in the mail with a destroyed pilot bushing and knackered throwout bearing. Ended up paying out of pocket to replace both because Luk won't accept partial returns; you need to return the entire kit and take your chances that your replacement kit comes through undamaged.

 

Sorry to hear your kit was buggered up, I thought the Luk kits I've gotten in the past to be well packaged, however its heavy parts and crappy shipping services that most likely caused the issue..

You'll be happy with the Luk kit. It made a world of difference in both my trucks, so much easier to drive than the stock DMF or whatever Southbend kit that was in my '93 from a previous owner.

 

I watch yours vids, I'm happy you're here, I'm looking an a 1986 f350 crew cab dually 6.9(Turbocharger) with a 2spd rear end. I'm wondering if a zf5 would be a better transmission for towing, I'm more worried about heavy duty towing and dealing with hills rather than gas mileage since I have made a lot of black diesel, I just haven't had a truck to run it yet. I don't ever plan on going any faster than 75mph and that's just because of Texas highways.

 

What trans do you have now?

thanks

 

It's the t19 I haven't driven the truck yet because I bought it with a bad clutch. But it's a 4spd manual so t19 I assume

 

I think I'd be trying the T19 out before going through the trouble and expense of swapping in a ZF5.

 

I recommend using Novak's gearing calculator to help understand the RPMs of having an overdrive gear or not. Also, they have a crawl ratio calculator as well for the low end. As far as the T19 vs ZF 42 vs ZF47 debate goes, the T19 in most cases is geared similarly to the ZF42 sans the overdrive gear. The upgrade to the 5 speed is worthwhile even for any troubles of modifying driveshafts and getting another trans tunnel cover for the floor hump; but you need to be sure whether your truck has a speedometer cable or a vehicle speed sensor (VSS) on the rear axle. For whatever reason, Ford decided that it would be no harm to gear a 1-ton truck like a jeep; but maybe if you have a 4.11 or lower rear it's not so bad... With a 3.55 rear and a close ratio ZF42, a load can be annoying to get moving out of first or reverse if on an incline or loose surfaces. I am currently in the process of doing a 4x4 swap on my '92 and while I haven't yet tackled the front end, I've replaced my old 2wd 42 with a 4x4 version that is a 42 with the wide ratio and I can say that it's pretty solid down low and up high so far. In 1st, I can't do much more than maybe single digits mph and the engine is screaming, yet at highway speeds in 5th and running 70mph or so, the IDI turns around 2000 RPMs. Running a wide ratio ZF is very similar to an NV4500 except you have gear noise, but don't have to worry about 5th gear failing.

 

So I know it has a 2 SPd rear end in it, which a big thing for me since I do a lot of heavy pulling, and I'm in East Texas so lots of hills. I'm trying to learn about the rear end and what the gear ratios are. But I don't plan on ever going more than 70-75mph, it would be nice to be able to get a load up to 65-70mph since on longer travels I have often found myself on I20. I'm not worried about gas mileage, I'll be making my own diesel and burning filtered oil products. I guess what I'm really asking is if the t19 or zf is a better transmission for low end grunt pulling. If the zf is better I'll do it since it's also my favorite bidystyle truck an I plan to own it when I die