5 speed vs 6 speed question (not gear related)

[USAFguy22]

So my '91 5spd tranny has about 60k on the clock and sometimes is hard to shift. It's not in the snap ring range and its only difficult sometimes when driving hard, fine when cruising and shifting slow. My guess is the syncros are a little worn, possibly from previous owners beating on it? To explain the problem some more; when shifting from 2nd-3rd and sometimes 3rd-4th it won't go in gear and may take a second attempt before engaging. Sometimes ill put it back in neutral and double clutch before re-engaging. I currently have the gm synchromesh cocktail and it helped smooth things out a bit. I've driven other manuals and gear changes are so much easier (my focus for example). Ill eventually want to fix the problem down the road and have to make a choice, will a rebuilt 5 spd shift and feel the same as a 6 spd with its dual cone syncros?

Thanks in advance, I've poked around on the search but I mostly get threads about gearing and highway rpm.

-Ky

 

[scammy]

sounds a bit similar to mine but i mainly have 2nd to 1st issues and 4th to 3rd so all down changing, i just run the OEM gearbox oil.
i just put the damper delete on off the NSX R and am going to play with the clutch adjust before i look at syncros, so interested in what others say

 

[USAFguy22]

I also have the 2nd-1st issue, which is bothersome because if I'm cruising and shift into second at like 20 I'm pretty much screwed if I want to stomp on it. Too low in the rpm to make boost and too fast to shift into first. I call it the "black hole". The chink in the nsx armor (pun def not intended).

 

[shawn110975]

I would try changing tran oil. there is oil we call the " cocktail " its a mixture of GM Syncromesh Friction Modified 2 quarts 1 quart of regular GM Syncromesh

this mixture changes as the tran heats up. after my 92 was having issues with second being a little harder to get into gear I tried this " cocktail " and it fixed the issue.
the tran felt like butter. so I went and did this to all my cars.

I have a 6-speed tran in my 92 now and only use this even though the tran has low miles.

other say honda whitecap lalalalla cuz they have not tried the cocktail.. if they did they wouldnt say whitecap lalalla anymore LOL

try it if it doesnt work and still having the same issue get the tran looked at or switch to a 6-speed like I did. its night and day

 

[Hugh]

Might need a cable adjustment as described on page 13-5 of the service manual.

 

[USAFguy22]

As stated above I have the cocktail already and it def improved the feel. I certainly recommend it.

 

[shawn110975]

sorry i missed that you already had it im tired long weekend

 

[Hugh]

Whatever you do, DO NOT PUT ZMAX INTO YOUR TRANNY!

 

[tof]

Yes. Cable adjustment. Or possibly a clutch master or slave cylinder issue?

 

[nsxtasy]

I had the same problem, although in my case the difficulty in shifting was primarily between third and fourth. It can be due to wear on the gear itself, on the synchro, or on the hub selector. These are all pieces inside the transmission, with teeth that are nicely squared off when new, but which can wear down, especially if the driver is not good at matching revs when shifting. The hub selector engages first, then the synchro, then the gear itself, and the parts tend to wear in the same order. Once the transmission is opened up, your mechanic can inspect the various gears, synchros, and hub selectors, and replace whichever one(s) are worn. You DON'T need to replace parts if they're not worn; for example, you can replace just the hub selector, or just the hub selector and synchro, without replacing the gear itself if it's not worn.

For more details, see this topic.

The gears, synchros, and hub selectors are all sold separately, although some of them are used for more than one gear (for example, the same hub selector is used for third and fourth gear). Below is the parts diagram for gears for a '91; you can click on it to view the part numbers and prices on the Acura of Peoria website. These are the items that can wear for third and fourth gears, using the numbers in the parts diagram below:

2 - third gear

7 - third gear synchro ring ("synchro")

9 - third gear synchro spring

5 (two pieces) - third/fourth gear synchro hub ("hub selector") on the right, third/fourth gear synchro sleeve on the left

9 - fourth gear synchro spring - I assume this has the same diagram number as that for third gear because it is the same part number

7 - fourth gear synchro ring ("synchro") - I assume this, too, has the same diagram number as that for third gear because it is the same part number

3 - fourth gear

You can find the corresponding parts for first and second gears as well. Same idea, same problem, same fix.

Also check out page 13-23 in the '91 service manual, which has the names of all these parts.

 

[USAFguy22]

I had the same problem, although in my case the difficulty in shifting was primarily between third and fourth. It can be due to wear on the gear itself, on the synchro, or on the hub selector. These are all pieces inside the transmission, with teeth that are nicely squared off when new, but which can wear down, especially if the driver is not good at matching revs when shifting. The hub selector engages first, then the synchro, then the gear itself, and the parts tend to wear in the same order. Once the transmission is opened up, your mechanic can inspect the various gears, synchros, and hub selectors, and replace whichever one(s) are worn. You DON'T need to replace parts if they're not worn; for example, you can replace just the hub selector, or just the hub selector and synchro, without replacing the gear itself if it's not worn.

For more details, see this topic.

The gears, synchros, and hub selectors are all sold separately, although some of them are used for more than one gear (for example, the same hub selector is used for third and fourth gear). Below is the parts diagram for gears for a '91; you can click on it to view the part numbers and prices on the Acura of Peoria website. These are the items that can wear for third and fourth gears, using the numbers in the parts diagram below:

2 - third gear

7 - third gear synchro ring ("synchro")

9 - third gear synchro spring

5 (two pieces) - third/fourth gear synchro hub ("hub selector") on the right, third/fourth gear synchro sleeve on the left

9 - fourth gear synchro spring - I assume this has the same diagram number as that for third gear because it is the same part number

7 - fourth gear synchro ring ("synchro") - I assume this, too, has the same diagram number as that for third gear because it is the same part number

3 - fourth gear

You can find the corresponding parts for first and second gears as well. Same idea, same problem, same fix.

Also check out page 13-23 in the '91 service manual, which has the names of all these parts.

Very helpful thank you! Now I'm still curious on how a 6speed tranny feels when shifting.

 

[scammy]

Legend Ken, thanks for the info will be checking these parts when i drop the engine later this year