xviper

I can't find the thread that these pics were originally meant for, so I'm just starting a new one.

Woodwork sent me these to post along with the following comments:

"The Sleeve teeth should be pointed, this is what grinding will do." ->



"6th side damage" ->



"5th side pointy" ->



I'll let Woodwork made any additional comments (if he so desires).

Woodwork

Thanks xviper,

Pointy is good, Mushroomed is bad.

The usual customer complaint is that the transmission won't go into 5th gear.

This part is the 5-6 shift sleeve. When it slides one way, the transmission is in 5th gear. When it slides the other way it is in 6th gear.

The cause is driving the car high RPM in 1st, shift into 2nd, then high rpm into 3rd. At this time the engine is screaming it's song and the driver usually feels the need to bring the engine RPM down so he (she) shifts into 6th gear and drops the RPM 3 or 4,000.

The problem is that 6th gear synchro isn't made to work that hard. (What is 5 to 6 RPM change? About 800 RPM?

When that happens the sleeve slides past the synchro that is over worked and grinds into 6th gear. This will mushroom the "Dogs" on the 6th gear and on the sleeve. When the clearance between the sleeve and the hub that it rides on is small enough then the sleeve won't slip backwards into 5th.

I'll send xviper more photos showing both main shaft and countershaft.

HTH,
woodwork

JL9000

sca037

Excellent photo and information....thanks!
Under your scenario (high rpm differential from 3rd to 6th) is the problem reduced if one allows the engine revs to drop to the appropriate level before engaging the taller gear, or does the transmission HAVE to be brought up to speed via double-clutching to make the match?

Brian

davepk

I lost 6th gear by missing my 4 to 3 down shift and hitting 5th instead. Do that enough times and say bye bye to 6th gear.

An interesting side note:

6th gear recently and suddenly started working again all on its own. I had the tranny out during an engine swap and when the tranny was reinstalled 6th gear was back.

I've always thought that there were 2 likely failure modes for the synchro sleeve gear combo. The one mentioned above and a different one that i think i actually suffered from.

When the sleeve is moved when engaging a gear it must first compress a circular wire spring that rests in a groove between the synchro hub and the synchro. If any bit of debris gets under the spring it can get stuck there and prevent the spring from compressing enough to let the sleeve slip over it. If after some time the bit of debris works its way out then the gear will suddenly be restored.

Big Ben

[QUOTE=Woodwork,Sep 22 2004, 11:13 AM] Thanks xviper,

Pointy is good,

xviper

Woodwork has loaded some pics into his gallery but he's not sure how to post them. So here is a link to his gallery and you can click on the photos you like to see the full size version (they are actually quite spectacular pics):
https://www.s2ki.com/forums/index.php?act=m...bum&album=11975

Here is a sample of what you'll see:
mainshaft countershaft and shift forks

mikegarrison

Wow, third gear seems pretty well chewed up. Is that what caused the removal?

Strike

This particular issue is a sore spot for me. Before I make any comments I just want to say that nothing I'm going to say is directed at Woodwork. Woodwork is a great guy (I've met him) who has treated the S2KI community very well with his insight and advocacy for us within Honda.

I believe the S2K tranny was under engineered, especially 5th and 6th gears. I also lost 6th gear about a year and a half ago. Have I ever skipped a gear in the S? Undoubtedly. However, I didn't do it much (never do it now that I know how fragile it is) and usually let the revs drop before actually engaging the higher gear. But I've skipped gears in every manual transmission car I've ever owned and never had a problem. Most people I know look at me funny when I say that Honda suggests not skipping gears.

I track my car. I've probably been much harder on gears 2-4 than 5 or 6. Yet the 5/6 sleeve was majorly thrashed when I got the parts back from Honda. The rest of the tranny looked brand new. I wasn't THAT hard on 5/6 and didn't skip gears THAT much. Unfortunately, we'll never know whether I caused the damage to my tranny or it's just not engineered to handle the type of use it's seeing. More unfortunately, Honda has taken the stance of "if there's tranny damage, it's ALWAYS abuse", and that's where my problem lies.

As a side note, I sued my dealership and won , and I would have been willing to pay half.

teamking

I heard this on NPR and then just Googled to find this article...

BMW X5 Airbags

The long and the short of it is that BMW X5's appear to be having a problem with their airbags randomly deploying. The dealers will fix it for you, but only if you sign an agreement not to tell anyone about it.

If it's true, that's really bad.