Zf6 issue.
 

So a buddy of mine has an early 99 with the zf6, it doesn't shift down from third but if you shift up to fourth you can shift down fine. He seems to think it's just needs new fluid but what else could it be, I need to know for sure because I might be trading my gasser for it this Saturday. I appreciate it.

Syncros

How would I fix them if that's what ends up being the problem? Because as soon as I trade I'll be taking it to service all of its fluids.

Transmission has to come out, not sure exactly how to change them, I've never done it before

Alrighty, I'll update it when I get the truck most likely.

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