How do you check out a ZF that is not installed in a truck??

[masterbeavis]

Just wondering. I bought a parts truck, with a ZF. Truck was high mileage, at least 340K based on the oil change sticker on the door. I got the trans cheap enough that at this point, if it needs a rebuild, the pain in the wallet wont be so bad. I was staring at it, it made me wonder if there were any checks aside from examining the fluid, shifting it thru the gates, and turn the input and output shafts. Is there a secret to inspecting these things without disassembly? What is a normal lifespan of one of these units if they are not abused?

 

[Greg77]

I got a used one and put in one of my trucks. WE changed over to a Luk clutch and took it out to change clutch. I had a guy working for me that had little or no brains. I told him how to take it out, this was a restored truck no rust, no grease, but he knew a better way. Long story he dropped it put a crack in the case. Took it up to the transmission shop I use, he said he thought he could weld it. He had a used case so he just decided to switch cases. I asked him when we picked it up what it looked like. He said you almost have to take it all apart to see what shape it's in. If yours has that many miles with no work done it is probably fairly worn with some bad syncro's. If you have a good shop they can be rebuilt for around $750 to $900.

 

[Devilish]

Greg is right, only way to truly check it out is to crack it open. At that point I think you should freshen it up anyways.

 

[Greg Pettit]

If the shafts don't have obvious bad bearings, and the shifter moves smoothly, I would consider installing it and testing it in your truck.....

It's only a couple of hours work to get the trans in/out, so for very little investment you have a great test to see what condition the trans is in.

Even if the trans doesn't work right, you now have specific problems to address instead of just rebuilding in the blind.

Good luck with it,

Greg