WARNING: DO NOT FLAT TOW A ZF5 EQUIPPED TRUCK

IDI For Life

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As the title reads, it's a bad gamble to flat-tow a truck with a ZF5. Not all manual transmissions are alike, so you may be wondering why the ZF5 can't be towed. And the reason is because there is no lubrication to the internals apart from the INPUT SHAFT turning. The Input shaft only turns when the engine is running.

My example is a personal one. I just recently purchased an F-Superduty (1992) with a zf5. I drove it, and the transmission was fine. It had a major turbo leak (uppipes we believe) so I didn't drive it home. The previous owner towed it home for me using his F450 and a tow bar bolted to the front of my truck (bumper removed). Upon starting the truck, when releasing the clutch, the engine died, even in neutral, and we couldn't select any gear whatsoever. It was stuck in neutral.

The input shaft bearings were welded solid. So unfortunately I have to yank the transmission out and rebuild it. The P.O. "thought" about pulling the driveshaft, but did not, so he felt really bad about that and we have since made arrangements for how to handle the matter, which was top notch on his part.

There are (4) 12-point bolts to remove the driveshaft from the axle yoke. This would have saved us a lot of heart ache, but neither one of us, nor any of the P.O's IDI/ZF5 buddies would have thought it an issue, until reading various forums and what not.
So, this is just a refresher for anyone scrolling the pages and curious as to whether or not to leave the driveshaft attached.
The answer is a resounding NO. Drop the shaft, save yourself the headache!


Jesus saves. Romans 10:9-10
 

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Azidiguy

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The exeption to this would be if its a 4x4 and the t case is in nuetral. That way the zf is not turning at all.
 

Jesus Freak

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As the title reads, it's a bad gamble to flat-tow a truck with a ZF5. Not all manual transmissions are alike, so you may be wondering why the ZF5 can't be towed. And the reason is because there is no lubrication to the internals apart from the INPUT SHAFT turning. The Input shaft only turns when the engine is running.

My example is a personal one. I just recently purchased an F-Superduty (1992) with a zf5. I drove it, and the transmission was fine. It had a major turbo leak (uppipes we believe) so I didn't drive it home. The previous owner towed it home for me using his F450 and a tow bar bolted to the front of my truck (bumper removed). Upon starting the truck, when releasing the clutch, the engine died, even in neutral, and we couldn't select any gear whatsoever. It was stuck in neutral.

The input shaft bearings were welded solid. So unfortunately I have to yank the transmission out and rebuild it. The P.O. "thought" about pulling the driveshaft, but did not, so he felt really bad about that and we have since made arrangements for how to handle the matter, which was top notch on his part.

There are (4) 12-point bolts to remove the driveshaft from the axle yoke. This would have saved us a lot of heart ache, but neither one of us, nor any of the P.O's IDI/ZF5 buddies would have thought it an issue, until reading various forums and what not.
So, this is just a refresher for anyone scrolling the pages and curious as to whether or not to leave the driveshaft attached.
The answer is a resounding NO. Drop the shaft, save yourself the headache!


Jesus saves. Romans 10:9-10
I would have never considered that. Thanks for the info. And Jesus sure nuff saves!
 

Booyah45828

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Very few vehicles should be flat towed. Unless it specifically says it can, work under the assumption that it can't. It has to do with fluid flow/pumps being on the output shaft. If it's splash lubed, or has the pump on the countershaft(zf6) it shouldn't be flat towed, as it won't be lubricated. If you can start it and idle it, that'd work. But most of the time you're flat towing because you can't.

If your vehicle is capable, I've always worked under the assumption it's with the T-case in neutral and the engine in gear or park. Very few transmissions have an output shaft oil pump.

I've pulled a lot of dead vehicles into the shop, never disconnected a driveshaft, but we never go far either.......
 

Azidiguy

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Very few vehicles should be flat towed. Unless it specifically says it can, work under the assumption that it can't. It has to do with fluid flow/pumps being on the output shaft. If it's splash lubed, or has the pump on the countershaft(zf6) it shouldn't be flat towed, as it won't be lubricated. If you can start it and idle it, that'd work. But most of the time you're flat towing because you can't.

If your vehicle is capable, I've always worked under the assumption it's with the T-case in neutral and the engine in gear or park. Very few transmissions have an output shaft oil pump.

I've pulled a lot of dead vehicles into the shop, never disconnected a driveshaft, but we never go far either.......
I used to run a wrecker for a while, and towed lots of 4x4 zf rigs tcase in neutral trans in gear
 

IDIBRONCO

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The problem with towing with the transfer in neutral and the transmission in gear is that if, for some reason, the transfer happens to pop into gear, you get a loud bang. The you're looking for another transmission and transfer case. It's better to leave both in neutral. The chances of happening are very small, but I know a guy who had that happen to him.
 
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