Dave_Nevada
New member
Howdy folks, I'm new here.
I haven't seen much on the topic of ZF6 transmissions here, so I thought I would start posting some of what I ran into during my refurbishing/rebuild/repair of the ZF6. I have a ton of pictures I took along the way, first hand experience in tackling this job, and stuff I learned along the way. Part numbers, how many to order, cost, source, etc. I kept a spreadsheet log of cost and information related to tool acquisition, components required and repair manuals needed to rebuild the ZF6. The stuff I have will work for 2wd or 4wd.
Okay, so lets get to it.
I will shoot straight to the bottom line on symptoms and cause.
1st off, I could no longer easily shift into gear. It got so bad that I had to shut off the engine to put it in 1st gear.
That turned out to be a worn out master cylinder shaft on the pedal tree, along with a worn pressure plate. The master cylinder shaft was fixed with a heim joint setup, and the pressure plate was fixed with a new HD clutch pack setup from Val-Air of Texas.
Next, the unit would not shift into 3 or 4th gear. When you tried, it just ground the gears.
That turned out to be the synchros on the 3-4 gear set, one of the springs and retainer plates had dropped out of the synchro housing. Luckily for me, they ended up stuck on the interior magnet that ZF installs in these things for debris.
Next, the trans had a loud and annoying gear rollover when in first or reverse. :doh:
That turns out to be bearings and a proper pre-load setting during installation.
Lastly, I decided to replace the main front case because it had cracks. apparently this is due to driveline problems. I'm not sure about that cause, but it's what I've heard. anyway, I replaced the main front case and had the driveline reconned at Bay Shore Truck here in Reno.
As an aside, I also replaced the leaking up-pipes with a set of stainless bellowed pipes from Riff-Raff in Oregon. I only want to do that job once, so I went with the best I could find.
As for the details of the ZF build, I will start posting to let you know what I did.
I haven't seen much on the topic of ZF6 transmissions here, so I thought I would start posting some of what I ran into during my refurbishing/rebuild/repair of the ZF6. I have a ton of pictures I took along the way, first hand experience in tackling this job, and stuff I learned along the way. Part numbers, how many to order, cost, source, etc. I kept a spreadsheet log of cost and information related to tool acquisition, components required and repair manuals needed to rebuild the ZF6. The stuff I have will work for 2wd or 4wd.
Okay, so lets get to it.
I will shoot straight to the bottom line on symptoms and cause.
1st off, I could no longer easily shift into gear. It got so bad that I had to shut off the engine to put it in 1st gear.
That turned out to be a worn out master cylinder shaft on the pedal tree, along with a worn pressure plate. The master cylinder shaft was fixed with a heim joint setup, and the pressure plate was fixed with a new HD clutch pack setup from Val-Air of Texas.
Next, the unit would not shift into 3 or 4th gear. When you tried, it just ground the gears.
That turned out to be the synchros on the 3-4 gear set, one of the springs and retainer plates had dropped out of the synchro housing. Luckily for me, they ended up stuck on the interior magnet that ZF installs in these things for debris.
Next, the trans had a loud and annoying gear rollover when in first or reverse. :doh:
That turns out to be bearings and a proper pre-load setting during installation.
Lastly, I decided to replace the main front case because it had cracks. apparently this is due to driveline problems. I'm not sure about that cause, but it's what I've heard. anyway, I replaced the main front case and had the driveline reconned at Bay Shore Truck here in Reno.
As an aside, I also replaced the leaking up-pipes with a set of stainless bellowed pipes from Riff-Raff in Oregon. I only want to do that job once, so I went with the best I could find.
As for the details of the ZF build, I will start posting to let you know what I did.
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