Once my truck is warmed up I literally have to force it in first gear everytime an to go in reverse the gears never stop spinning so I have to kill the truck an put in reverse crank back up an go. I replaced slave cylinder today with no luck any ideas?

 

check your clutch pedal bracket, they sometimes crack so they bend when you press the pedal and you don't get full throw on the rod.

 

Ok will do when I bout the truck I checked tranny fluid an was full but dirty would that have something to do with it

 

That's a possibility. If the synchros aren't syncronizing it can be hard to shift, but (someone correct me if I'm wrong here) I don't think 1st or reverse have synchros. Still, changing the oil in the tranny can only do good so I'd start there.

 

What weight gear oil an how much?

 

I think it's 80-90 and around 5 quarts, but I'm not positive on that. Make sure you get it with the PL-5 or GL-5 or whatever it is additive for synchromesh gearboxes. The FSM can tell you, I don't have mine handy right now, but if you don't have one someone else here will know.

 

Best thing I did was put redline mt90 synth (GL4) gear oil in my w56. Previous owner had some thick oil in there and it shifted like crap. New oil and it is good as new.

Pull back the carpet and see if the master is leaking. Its worth checking out. Def check the pedal bracket, I welded mine before I did my swap.

 

Be sure you verify which lube you need. GL-4 or GL-5. GL5 can sometimes do some damage to the soft(brass) metals inside the trans. The additives in some GL5 lubes will corrode the synchros into oblivion. From what I have researched Redline MT90($$) is the best GL4 out there, which is what my swapped '87(?) W56B calls for. I have Lucas 75W-90 GL-4/GL-5 in there now and it shifts ok, but a little clunky sometimes. I will be doing MT90 very soon to see if there is a difference. Good luck!

In regards to your question, I 2nd the notion to check the clutch master. Sounds more like a clutch not entirely disengaging issue.

 

If the gears keep spinning when the clutch is pushed in, gear oil weight and syncros have nothing to do with it, It more likely the bracket that Bingle spoke of or the master cylinder is bad.