Hey everyone,
Just put a V8 WC T5 into my car that I purchased used from a board member. I used a new clutch kit during the install. After getting it all back together, I found that the trans is grinding going into 3rd & 4th gears. All other gears are as smooth as silk. And once im in 3rd or 4th you would never know there was a problem. Any thoughts? Did i get boned on a bad trans? Or could it be my clutch install? I really dont want to take the trans back out. My chest still hurts from letting the trans rest on it while taking it in/out. Im going to go drain the fluid & put new stuff in right now. Im hoping that will solve the problem.


Thanks in Advance,
Mark B

Oh... And it grind while downshifting & upshifting.

 

You've got a bad synchronizer assembly. Probably both rings and the hub/slider. There's a possibility that the gears have damaged engagement teeth too. The only way to know for sure what's bad is to crack the trans open. PM me if you're looking to have the work done.

 

Probably not the transmission itself.

What kind of pilot did you use; a bushing, or a bearing?

 

If the problem was exclusive to 4th gear I would be inclined to agree with you, but since the problem presents itself in 3rd gear as well there is something wrong in the transmission. When you shift from 2nd to 3rd the 1/2 fork returns to the neutral position and the 3/4 fork moves to engage 3rd gear. Since the input shaft and mainshaft are not being directly coupled the effects of a bad pilot bushing/bearing would not be felt when shifting into 3rd gear, only when shifting into 4th where the two shafts are mechanically coupled.

 

A bad/missing pilot affects the operation of the 3/4 sleeve in BOTH directions of its motion. Far worse in 4th usually, but it can affect 3rd also, especially if the extension housing bushing is also loose, and the shafts can flop around in there more than usual. That can keep the keys from working the way they're supposed to.

And in a conversion situation, leaving out the pilot, is a VERY high probability mistake to have been made.

As another member of this board that I haven't seen for a while, much smarter than me, used to say, "the simplest explanation tha tfits all the facts is usually the right one". Seems like that would apply here.

I think troubleshooting should start at the pilot.

 

think i'm going to have to agree with tko, but we need more facts, does the clutch chatter when taking off? did you put a pilot bearing in when you installed the clutch?

 

Clutch is quiet. New bushing was installed.

I have noticed that 3rd & 4th dont have the same "feel" as the other gears do. With the other gears you can feel that the trans is in gear when you move the shifter. Theres that point in the shifter motion that puts up the smallest amount of resistance. 3rd & 4th dont have that feel the shifter moves into gear with no resistance what-so-ever. Hopefully you guys know what im talking about.

 

Well then, if the bushing is good, it pretty much has to be inside the transmission.

Most likely it's broken 3/4 synchro keys.

 

If there was no pilot bushing maybe 3rd could be affected. I think the bushing would have to be sloppier than any I've ever seen to have it affect 3rd as long as there is a bushing in there. When the slider is in the neutral position on the hub it is only engaged with the synchro rings on the input shaft and the mainshaft. The input shaft would have to be cocked at a horrific angle to make the slider not want to come off the input shaft ring to the point where it would grind. Typically with a bushing, even one with 100,000 miles worth of wear there isn't that much play. Bearings, on the other hand never seem to go bad. I always replace them with a clutch job as a matter of course, but they seem to last almost indefinately.

It is right to point out that to correct this problem the trans has to come out anyway, so inspecting the clutch components is a good idea. If the bushing is new, as indicated, I think you can safely rule it out.

 

I'd have to agree that it sounds like the synchro keys, especially when you point out that there's almost no resistance when shifting into 3rd or 4th. I'd say it's a pretty safe bet you'll find either broken or whole keys lying in the bottom of the case where the magnet is. I'm not as knowledgeable on the T5's as I am on Muncies, but the synchro keys in a Muncie are what gives you the detents and the proper "feel" when shifting into a gear. I had one shift just like you described at one point in time, and the synchro keys had broken and fallen out of the slider/hub assembly. This same problem can also trash the engagement teeth on the slider in a hurry too since the keys help the slider stay centered with the synchro assembly.

 

Synchro key failure is fairly uncommon in T5s. I think I've only ever seen one or two T5s with this problem. By contrast this problem plauges T56s, especially the 3/4 keys. This is why billet keys are available.

Regardless of the cause teardown is the only way to know for sure what's wrong. Even if the problem was minor, the grinding indicates that at this point there is probably damage to the hub/slider or the engagement teeth on the speed gears, or both. Just fixing the obvious flaw and slapping the trans back together is a sure way to have more problems down the road (not that this is what anyone here is suggesting, but plenty of people would advocate this).

 

Im just going to get another one & have it gone through before I put it in the car. I cant take this one out and have my car down for a few days. Now that my beater is totaled, I need my camaro to get to work. Plus, with all the dammage this trans probably has. It would be cheaper to just buy another one.