Q: What happens when you hammer it in third?
 

A:

http://forums.pelicanparts.com/uploa...1213056073.jpg
http://forums.pelicanparts.com/uploa...1213056125.jpg
http://forums.pelicanparts.com/uploa...1213056149.jpghttp://forums.pelicanparts.com/uploa...1213056214.jpghttp://forums.pelicanparts.com/uploa...1213056277.jpg

That's why I always hammer it in 2nd when autocrossing.

Is the 3rd gear smaller or weaker than 2nd?

Thanks,

No, it comes down to personal preference... that is, what is the preferable gear to smoke a Corvette. LOL

Are you sure you don't mean:

Q: What happens when you hammer it INTO third?

Are you sure you don't mean:

Q: What happens when you hammer it INTO third?

Why would you want to hit your 3rd gear with a hammer? You must not like it very much. Try swapping the ratio if you are unhappy with its character. Until then, it will work much better if you turn it, not hit it.;)

I should have named this post, "What happens when you let your girlfriend drive your Porsche!".

(I hope my girlfriend isn't surfing Pelican in the next room)

That's most definitely NOT from hammering it while in third. That could never happen. It's from hammering it into third.

Nope

Those little dog teeth are the things that break off when you force a gear. The damage above is what happens when one of those little dog teeth get between the driven gears! Any other damage??

high hp and 25 year old machinery (that also had an affair with a 3.8 some time ago) is a troublesome combo...

not really. the dog teeth are fine. the prob was really isolated to the 3rd gear set.

yep.

Dentist's asking about the condition of the teeth on the idler gear that is the mate to the gear you have posted. It's pretty rare for teeth to just fracture off the main body of the gear without an instigator. The instigator is usually teeth breaking off of the engagement gear (or dog teeth) which is pressed onto the idler gear and is a seperate peice. Another common cause is for teeth to snap off of the operating sleeve as it engages with the dog teeth.

Either way it is still accurate to say that this is what happens when you hammer it into third, but this is the end result. The cause isn't pictured. Show us pictures of the mate idler gear and the op. sleeve and hub.

Yup.

Pics of girlfriend who slams Porsche into 3rd are required at this point ;)

http://forums.pelicanparts.com/uploa...1213070809.jpg

There she is!
http://forums.pelicanparts.com/uploa...1213070999.jpg

Didn't find any of these in the bottom of the tranny?

http://forums.pelicanparts.com/uploa...1213074849.jpg

mmmm.... crunchy! Coulda possibly come off a different gear, too. Hopefully none of the other gears choked on the debris. Don't forget to check the diff case carefully too!!

Autopsy findings:

Suprisingly the dog teeth had zero damage. Only remanants of third gear teeth came out of the case. The driver earlier described a 'ticking' in third gear which I believe was the first tooth (possibly partial) failure on third gear. When he 'hammered it' in third he took another tooth or two out and third gear was done.

Dentist90: Move to the front of the tranny rebuilder class (again). During the rebuild I neglected to clean out the diff. Fortunately I had the owner run the tranny for half an hour using an electric drill, the remaining debris came out in the ensuing flush (prior to driving the car).

Final conclusions: Too much torque, missed shift, or simple gear failure? I suspect third gear failed from too much torque. This 915 had a 3.8 on it for a while, now it has a 3.6, so long term it might fail again, espescially given the owners propensity to 'hammer it' on the track. :)

Never knew about the 3.8, but I have witnessed the owners propensity first hand....:D

Just out of curiousity but did this happen on an upshift or a downshift? The handful of instances when I have seen teeth rip off without the help of loose dog teeth it's almost always been a hard downshift with engine braking that's ripped them off.

Of course, even if it happened on the upshift, since it was ticking previous to the catastrophic faiilure who is really to know when the damage that cause the failure really occurred.

Bill Howard said he had a 3.8 in Ruby for a while, prior to going Varioram.

It began making a ticking noise while driving it on the street. The next track day killllllled it, since it's a mostly 3rd gear track.