T-5 Tranny Question

[rponfick]

I have a Mk4 Roadster with barely 1000 miles on it. The T-5 was new when installed, and has a slave cylinder hydraulic clutch.

I have a slight crunch each time I shift into 5th gear. All the other gears are smooth as can be. I thought it might be a clutch adjustment issue, but it only occurs shifting into 5th. If it were an adjustment issue would there not be some crunch in all the gears? Do the 5th-gear synchros need to break in somewhat?

I have purposely tried pushing the clutch in all the way when going into 5th, but it doesn't seem to help the issue.

Any comments would be appreciated.

Ralph

[MB750]

How soon after you bring the clutch pedal off the firewall does the clutch engage?

Right away? Half way up?

[cob427sc]

If the clutch isn't adjusted properly you would notice the problem in other gears, either the crunch because it doesn't fully disengage or the clotch slipping if to tight. Sounds like a synchro problem in the 5th gear which really doesn't require any break-in.

[Railroad]

Keep driving it. If it does not clear up, try a fluid change. If you know what lube you are using, change brands. Some of the guys swear by their favorites. Might have to do a search for the most popular. TKO's like GM syncromesh.

[rponfick]

How soon after you bring the clutch pedal off the firewall does the clutch engage?

Right away? Half way up?

Clutch engages about 1/2 to 2/3 of the way up. Does that give you any hints?
Ralph

[MB750]

Clutch engages about 1/2 to 2/3 of the way up. Does that give you any hints?
Ralph

Yup. It tells me there's absolutely zero chance the clutch is dragging, which could cause that issue.

I just went through a slave cylinder travel issue on my T5 so the topic is hot in my mind.

[AC Bill]

I doubt it is the clutch. As suggested, the synchro possibly, one of the keys is missing..The other thing is if you have a shifter with adjustable stops, it may require some adjustment.

[rponfick]

I doubt it is the clutch. As suggested, the synchro possibly, one of the keys is missing..The other thing is if you have a shifter with adjustable stops, it may require some adjustment.

I would hope not a synchro issue on a new T-5. The shifter is the internal mechanism on the top of the tranny, and I am not aware it had any adjustment stops. I will keep searching.
Thanks for the comments.

[AC Bill]

Some of the commonly used aftermarket shifters have that adjustable stop feature, Hurst for example.

[Dgc333]

The adjustable stops are to keep you from slamming the shift forks when aggressively shifting by stopping the shifter handle before you over stress the forks. If not properly adjusted you may have an issue with it not staying in gear but it would likely effect third gear too.

[cob427sc]

I'm still in favor of it being a synchro issue. If the tranny is still under warranty it would be time to pursue that route. Otherwise, I would drive it and maybe with fingers crossed it will go away. Only other alternative is to open up the case and see what's wrong. The shifter stops wouldn't create a crunch when shifting, only prevent full engagement of the gear if improperly adjusted.

[rponfick]

Keep driving it. If it does not clear up, try a fluid change. If you know what lube you are using, change brands. Some of the guys swear by their favorites. Might have to do a search for the most popular. TKO's like GM syncromesh.

Railroad, it may be time for first oil change. I have to get it up on the lift to see what type of T-5 it is. I understand the World Class takes a different fluid that the regular T-5. Is that correct and what are you guy using in either type?

PS: Just checked tag on tranny - 1352-257-17682. I had read where it should end with a "Z" if world class, but has torx bolt head on drivers side which is supposedly indicative of WC. So I am currently confused as to which tranny I have.

Thanks, Ralph

[Hellion]

I'm still in favor of it being a synchro issue. If the tranny is still under warranty it would be time to pursue that route. Otherwise, I would drive it and maybe with fingers crossed it will go away. Only other alternative is to open up the case and see what's wrong. The shifter stops wouldn't create a crunch when shifting, only prevent full engagement of the gear if improperly adjusted.

I second this. Had the same issue on a '65 Mustang 2+2 with a new WC T-5 and it was the synchro.

[Railroad]

Railroad, it may be time for first oil change. I have to get it up on the lift to see what type of T-5 it is. I understand the World Class takes a different fluid that the regular T-5. Is that correct and what are you guy using in either type?

PS: Just checked tag on tranny - 1352-257-17682. I had read where it should end with a "Z" if world class, but has torx bolt head on drivers side which is supposedly indicative of WC. So I am currently confused as to which tranny I have.

Thanks, Ralph

I will defer to Mike Forte. He has probably dealt with more T-5s than I have seen.
WC takes something equivalent to auto trans fluid, you will need to chose the brand. Again Mike can probably give a recommendation with confirmation of results.
Non WC shows taking a 50w gear oil, so it will be imperative to determine which you have.
Mike can probably give you a definite answer from your findings.
I have read, NOT to use SYN ATF in T-5's due to damage to syncros.
If the trans was bought new and had fluid, I would put a lot of faith in what is in it, atf or gear lube.
Hopefully more experienced trans guys will chime in and confirm the right choice.

[Dgc333]

I have read, NOT to use SYN ATF in T-5's due to damage to syncros.

And I have read recommendations from the T5 gurus to use synthetic ATF. If the tranny was made after 2008 Tremec recommends their own MTF.

[MB750]

Dexron 2

[rponfick]

I will defer to Mike Forte. He has probably dealt with more T-5s than I have seen.
WC takes something equivalent to auto trans fluid, you will need to chose the brand. Again Mike can probably give a recommendation with confirmation of results.
Non WC shows taking a 50w gear oil, so it will be imperative to determine which you have.
Mike can probably give you a definite answer from your findings.
I have read, NOT to use SYN ATF in T-5's due to damage to syncros.
If the trans was bought new and had fluid, I would put a lot of faith in what is in it, atf or gear lube.
Hopefully more experienced trans guys will chime in and confirm the right choice.

From my recent research, it must be a WC. Gordon Levy stated that since 1985 they have all been WC. The dime-sized shaped star has 19 in it which I assume is a 2019. I found what appears to be a knowledgeable T-5 website called Moderndriveline.com. They rebuild and have a lot of good info on their site. They recommend Amsoil OE Synthetic Automatic Transmission fluid in the WC T-5, which conflicts somewhat with what you had seen. I have emailed them with my 5th shift question, so will keep advised.
Let the fun continue.
Ralph

[rponfick]

I changed the fluid to Amsoil OE Synthetic Automatic Tranny fluid, and it didn't make any difference. I still get the slight crunch going into 5th. Will keep driving as is and hope for the best.
I don't think it is worth the trouble of taking out the tranny and checking synchro over a slight crunch.
Thanks for the comments. Ralph

[rich grsc]

Try slowing down the shift into 5th. The 4th to 5th ratio spread is pretty wide, just try taking your time with the shift to see if it helps.

[Ford & Jeep Fan]

I changed the fluid to Amsoil OE Synthetic Automatic Tranny fluid, and it didn't make any difference. I still get the slight crunch going into 5th. Will keep driving as is and hope for the best.
I don't think it is worth the trouble of taking out the tranny and checking synchro over a slight crunch.
Thanks for the comments. Ralph

You are going to find it is just going to get worse over time.