I have a 84' Z28 L69/T5, I have replaced the NWC (after it blew). to a 90 WC.

The problem started after I had miss shifted 3-4 while driving.. I had not put it into 5th complete and as I power came on, it popped out of gear and the results were that only on Down Shifting from 5th to 4th it is hard to shift into and grinds, double clutching helps some.

Before I tear into it.. I am thinking that I bent a shift fork only.. as it is ok up shifting from 3rd to 4th and then into 5th..?

Trans is out now, new Clutch and resurfaced Flywheel... changed the oil pan gasket.. so now only the Trans is left to fix !

What do you guys think?, did I bend a fork or is there something else that could be wrong ?

thanks....

 

Pilot bearing...

I doubt the missed shift has anything to do with it. Coincidence. Remember, "correlation does not prove causation".

Oh did I mention, change the pilot bearing? That should be replaced as part of a clutch job, regardless; but it's particularly conspicuous by its absence from your list of activities.

Leave the transmission alone. 99% of all transmission problems, besides stripped gears or brinnelled bearings, are really clutch problems. The other 1% are clutch problems too. Virtually 100% of shifting problems, are clutch problems. Keep in mind incidentally, the forks in the T-5 are basically pot metal; they don't "bend", they just snap off. Works/doesn't. No in-between. If it works AT ALL, it's fine.

 

I am changing the pilot bearing this weekend, Have also replace the Flywheel and Clutch bolt with new ARP ones.

But I will have to at lease open the trans to replace the speedo gear on the output shaft.. So, at that point, taking the top cover off to inspect and replace a fork is not much more work. I don't know too much about T5 workings, but I have in the pass rebuilt many Muncies and T10. So I am not sure why the downshift from 5th to 4th is having problem.. but it is the only shift that is problem.. upshift to all gears is ok 1 through 5 and downshifting from 4 to 3 to 2 to 1 is ok.

I will inspect the old pilot bearing later once I have out.. it was the roller bearing type, which most likely by now has dried up.

Thank you for the recommendation and info.

 

It might be that the 4th gear syncronizer is shot if that is the only gear that is grinding. That happened to 2nd gear in my T56. Shifting to second would always grind but all other gears were fine. I tore the tranny appart and the friction material on the syncronizer was totally gone.

 

There seem to be on grinding on up shifts from 3rd to 4th and from 4th to 5th.. or from 4th down to 3rd..

I am going to take a look at the syncro's soon as I have finished the Oil Pan replacement, reinstalled the flywheel, clutch and Pilot Bearing. That bearing was a PITA to get out.. my slide happer could do the job, it broke two of my attachments.. I ended up grinding one side of the bearing to the point it was almost to the Crank, then used a center punch to knock it apart !.. did a good job of not damaging the crank.. so on to the Trans.. but waiting to see what the syncro's and forks looks like...

 

Well if your transmission is grinding in all those gears I doubt you have a syncro or shift fork problem. Sounds like the pilot bearing could definatly be the problem or maybe the clutch is wore out. Each gear has it's own syncro and I believe 4th and 5th use different shift forks so those things are probably fine. Since you already changed the pilot bearing you might want to reinstall the tranny and try it out. How does the clutch disc look?

 

No.. its just the 4 to 5 downshift that is hard.. I am aware of the working of a manual trans.. I have rebuilt many Munices, T10 and Ford Toploaders in the past.. but this is the 1st T5.. shouldn't be a problem. I just don't have a shop to use anymore, could use a press....

Clutch (CenterForce Duel Friction) wore well.. the Flywheel was a bit of un-even wear. Clutch disk had about .003 wear when compressed, but enough to make it slip under load due to the Flywheel wearing.

Have the tail end and top plate off.. blocking ring and Syncro's don't look bad.. still have (almost and I have seen wrost) sharp teeth, gears are good. Might just replace the pads on the fork for now, just to get it running and get a smog test before my Registration expires.(4/18).