LSD Tranny question

[rickyduckworth]

something that i've used to help alleviate the clunking is the GM synchromesh. i've used it in OEM honda lsd trannies, OEM gm lsd trannies, and aftermarket lsd trannies

[lowakkord]

Syncromesh has apparently been discontinued. So im told at work (GM dealer).

[cp[mike]]

i wondered why mine did the same thing... ill pay closer attention to when it does it.

[cp[mike]]

is this something related to helical LSDs only, or locking as well?

[TypeG]

if there is a problem inside the transmission, you can be assured it will get worse before it gets better. later.

[Chrisisiced]

Seeing as how this issue seems somewhat common i dont think its a big deal other than being annoying to hear everytime it does it.

Cpmike i didnt notice yours clunking at all
When my friends civic did it it was very loud and noticeable and i felt it through the steering wheel. I didnt know if somehow i broke something within 3 ft. or his axles were shot but my friend told me its always done that and thats just how it is.... I wouldnt worry about it until it starts to affect driveability.

[rickyduckworth]

Syncromesh has apparently been discontinued. So im told at work (GM dealer).

if that's true, there is still plenty left in house it seems.

quaker state and pennzoil (and probably others) make a basically identical product. a lot of the other brands aren't normal stock though, but can be ordered. GM always had the synchromesh in stock.

[owequitit]

WOW! Definitely good feedback.

Here are the exact symptoms. (I went out and did a test drive).

1) It only occurs in reverse.

2) It only occurs with a severe amount of turning lock in, such as all the way to one side.

3) It seems to only do it while I am making the rearend go to the right.

4) Occasionally, after I back up, it will give me a slight clunk when I first go forward, but not as big, and it hardly ever does this.

5) It does not "clunk" while turning at full lock moving foward.

6) All other LSD related functions are seamless. It doesn't pull funny, and when I get on it in a turn, there is nothing odd when it starts to transfer torque. It makes no other odd noises whatsoever.

7) It isn't leaking, all axles are seated properly etc.

8)Nail, I did do an auto to manual swap, but the axle is sitting in there, and has not come out.

9) Ricky: I thought about using syncromesh, but the new green label Honda MTF is supposed to have similar additives that are better for Honda trannies. Chemically, I don't know how true that was, but Honda specifically formulated it to do the same things Syncromesh does. I may still try it though.

The thing that seems odd is that it only clunks in one direction of travel, and with the wheels turned one way. I always figured if it was a shimming issue, the problem would be more widespread.

There is a smidge of bearing noise with the clutch out, so maybe the tranny was severely abused. It doesn't have any grinds or anything though, which I would have expected with severe abuse.

Thanks for the input, if anyone else has any ideas, I am happy to entertain them. I think I am going to put it on jackstands and check it out with the wheels in motion.

[owequitit]

if there is a problem inside the transmission, you can be assured it will get worse before it gets better. later.

Yeah, I am kind of thinking about looking for another one...

[wrichards2005]

Scott I just googled "LSD Clunk," try that theres a lot of people dealing with the same issues...

[owequitit]

Thanks for the link. It seems that the issue I am having may fall into the category of "normal."

I am definitely going to look into it more as I have time.

[wrichards2005]

Yeah it sounds normal to me... maybe ask 2point6 he might have a definite answer for ya...

[HondaFan81]

I wonder if this is a gear set backlash related issue? When you switch directions, common in trucks however they also have a long driveshaft connecting from transfer case/transmission to rear axle, so it is even more noticeable.

If it were a shim issue, this would cause noise in driveability as the differential needs to be properly in place or the gear contact pattern will always change on the fly and cause noise, especially under a good amount of load/torque.

[owequitit]

I wonder if this is a gear set backlash related issue? When you switch directions, common in trucks however they also have a long driveshaft connecting from transfer case/transmission to rear axle, so it is even more noticeable.

If it were a shim issue, this would cause noise in driveability as the differential needs to be properly in place or the gear contact pattern will always change on the fly and cause noise, especially under a good amount of load/torque.

It mostly just does it going the same direction with the wheels turned. It will sometimes give just a little bit of noise when changing directions, but mostly not. It doesn't do it if I roll straight back, or if the wheels are at less than about 3/4 lock.

[newtuner7]

dont know how relevant this is but i experience the same clunking in my truck with the four wheel drive engaged backing up and then right when i go forward... it has always done this and have never had any problems and the four wheel drive works perfectly... so yea just figured i would state that.