FM145 Input shaft play

[mnewman]

Greetings folks. I picked up a used FM145 for my '86 BII. There is a bit of play in the input shaft, like .010 or so. My question: is that normal or is that an indicator that it has excessive wear? The truck it was pulled from had 129K on it.

 

[Shran]

I'd probably run it. Those transmissions are kind of notorious for eating input bearings but I have rebuilt a couple and even those had a small amount of play there as well. There is another bearing inside the input shaft that can cause that slop though and it will also make a whining noise in all the forward gears except 4th if it's worn enough.

Valvoline Synchromesh MTF works really well in these, I would highly recommend it over gear lube.

 

[mnewman]

Thanks. That was what I was hoping to do. My current unit is a screamer so I'm hoping this one is better.

 

[mnewman]

I'm getting back around to this. I was concentrating on getting the interior back in it so I could recover some space in the shop/house. Anyway, noises have gotten worse so I need to get this done. Before I order a clutch kit... How / when is the 4.0 clutch upgrade worth it? I don't plan on doing much if anything to the stock 2.9 but I do plan on doing some trail junk with it. I've got a locker for the front and the rear is already a limited slip, I figure it'll end up with 31" tires on it after the lift is installed. I'm assuming my pressure plate is fine and the starter works so those are the only real differences in cost as far as the upgrade.

So is the 4.0 clutch worth it for a mostly stock BII?
Any tips for doing the clutch job? (This will be my first)
Do I need to replace the slave cylinder if it works and isn't leaking?

 

[Shran]

Others will probably disagree but I don't think the 4.0 clutch is worthwhile for a mostly stock vehicle.

Yes, replace the slave unless you know it's been replaced recently.

My tip is to plug the end of the hydraulic hose when you remove it from the slave, do not let fluid run out of it for very long or it will run the system dry and you'll have a hell of a time bleeding the air out

 

[mnewman]

Thanks Shran. I went ahead and ordered the 4.0 clutch, flywheel and starter. Although now that I think about it I ordered the slave for a 4.0... Not sure if should have stuck with the 2.9 stock version. I guess I will find out.