Chipped A Gear...How Long Until It Fails?

So I chipped first gear yesterday. Any guesses on how long before the tranny goes? It seems to have been a clean break and there is no niose in 2nd,3rd,4th or 5th. First gear wines like reverse under load and coasting, but there is no niose in neutral and coasting. I'm not planning on beating it into failure, but I am going to drive it for a while before i have it re-built.

 

Just wondering if anyone else has chipped a gear and how long it took before the grenade went off. The service manager at the dealership said it didn't sound too bad to him and recommended that I just take it easy on first and keep driving it until I'm ready to do the re-build. BTW I'm at 48K miles and the tranny has seen some aggressive driving, but has not really been abused anywhere near as bad as other cars I've had.

 

Also, i was told that it will probably be $1700-$1900 for a stock re-build from my local dealership. Does that sound about right?

How do you know its chipped?

 

And if so, how did you do it?

 

And why would you not want to get this immediately corrected?

6MT swap time!

6MT swap time!

+1

How do you know its chipped?

 

And if so, how did you do it?

 

And why would you not want to get this immediately corrected?

 

I'd like answers to these questions as well

I was at the track on Suday planning to do a couple runs so I could log with my WBO2 so I could compare them after I do a new tune. Now, I've been running this car for almost two years at the track. I always start off with a 2K gum-on-the-shoe clutch pedal release and work my way up to about 3K-3.5K RPMs as the day goes on. Usually I get a little tire spin and have even had some hop on higher RPM launches, but this time everything hooked up with no give at all and I heard a clunk. It isn't unusual for my TMIC to bump the hood or my DP to bump the firewall so it didn't phase me at all.

 

Didn't think much about it until I pulled in to park and put it in 1st gear. It made a little whinning noise as I coasted in first. I didn't do any more runs after that. I drove it 40 miles home with no problem and started checking things over. I checked the fluid and it was crystal clear as if it just can out of the bottle(new clutch last Sept) and full. I took off my AP Pitch Stop Mount and STI Group N trans mount to see if it was just noise from the LWFW that is real audible with the solid mounts installed. Stock mounts and it got quieter but still not gone.

 

Basically, it growls a little in first. It's fine under light even throttle, but gets louder with light or heavy throttle. First gear also growls rr..rr..rr.rr when coasting with the clutch in or out and kinda sounds like it's out of round. No other gears seem to have been effected by it. All other gears are fine with the clutch in or out and don't make any noise(well no more than usual).

 

Both the service manger and my prefered tech(20 year vet) said it sounded like a chipped gear. The tech heard it as we drove by him in the service bay and came up to us and said " that thing sounds like it has a chipped gear" and the SM said "that's what I was thinking". These guys see a toasted tranny at least once a week.

 

As for fixing it; It still drives fine with no bad vibes, just noise and will probably cost the same now or later. I'll probably fix it sooner than later, but just wanted to see how many miles everybody thinks it will make it before it grenades. BTW I made it almost 5 months on my stock clutch after it started slipping. I had the parts sitting in the garage, but I like to get all the life out of a part before I replace it:lol:. Another thing is that I had a Jeep Cherokee that made the exact same noise in 2nd gear and I drove it that way for over 60K hard miles and sold it to a buddy who still drive it daily so...

 

Attached is the timeslip from that run.

Maybe its just me but I wouldn't be able to sleep well at night knowing that there was a gear tooth floating around somewhere in my transmission...

 

Good luck though and keep us posted.

Well, gear teeth shouldn't float. They should sink to the bottom or stick to the magnetic drain plug. Believe me, if there was anything still rolling in the gears; I'd be getting it fixed today. From the way it drives and sounds; it's probably a small chip and a clean break. There was/is no metalic flakes in the gear oil and I'll drain that today so I can see if I can retrieve the tooth and try to get a picture.

 

I guess I've blown enough transmissions over the last 20 years that one more doesn't really bother me. I actually amazed that it held up this long. I'll probably just start searching for some PPG gears so I have them when it decides to pop. It really isn't that bad. You can't feel it, but you can hear it. I think my LWFW makes it louder too. I would bet that you wouldn't even be able to hear it with stock mounts and a OE flywheel installed. I'm going to try to make it at least a couple months before the rebuild so I can find and collect some gears.

 

So come on now people.

How many miles before she blows?

Do I need to add a prize for the person who gets closest?

Sometime when I shift 2-3 I feel a little snag. I can't recall ever grinding or mis-shifting and it doesn't take any effort to overcome... it just feels like a slight catch. I always thought it was a syncro thing, but your post has me worried. Thanks a lot!

The first to second grind/snag is pretty common in most manual trnasmissions with some miles on them. Second gear takes a lot of abuse. 1st-2nd usually gets slammed (merging) and missed more than other gears and a lot of people use 2nd gear to slow down too so it takes a bit more abuse than other gears. I know some pople have shelled third, but I don't think I've ever had a problem hitting third.

I had a 92 Cherokee that had a bad 2nd gear synchro and a chipped 2nd gear and I drove and off-roaded it like that for over 60K miles. You just have to be careful when shifting into second. Make sure the clutch is all the way down and just let it fall into gear, don't force it and you should be able to make it last quite a long time.

I don't know how long it will last, however the thing that makes this suck even more is that is not how you would check your AFR. Shifting throught the gears would bring in the affects of tip in. AFR should be verified on a 2K- redline pull in third.

Ya, It really sucks since my Street Tuner Advanced just arrived on Monday. If I would have gotten it Friday I'd still be tuning and this wouldn't have happened(well until later). I've got a TDC map running right now and it's O.K. It's knock free but rich as hell. The wideband just got installed last weekend so I was just planning to log a little on the highway during the roadtrip to the track, make a couple passes and log those and be done.

It was just real wierd that it popped when it did. Although about a month ago I went out to the track when it was still pretty cool yet and I was breaking the tires loose in the middle of 1st and 2nd gear. I only got 3 runs in that night, but on the last one I got a lot of wheel hop. After that I installed my F/R sways and endlinks along with a AP pitch stop mount.

This time at the track it was warmer and during the day so the track was a lot stickier than at night. The tires didn't spin at all no even a little and I didn't get any hop. It just hooked up like never before. I really didn't even launch it that hard. No worse that pulling onto a highway from a dead stop during rush hour. It's not like I pegged it to the rev limiter and dumped it. It was just supposed to be a feeler run.

 

So now I have a brand new copy of ST-A, a freshly re-built DB TD06H-20G sitting in the kitchen and a bit of a wait before I can really do anything with it either.

I drained the tranny today and didn't find any chunks, a lot of flakes and some slime, but no chunks on the plug or in the pan. Refilled it and it sounds better, but 1st is still has a little whine when coasting. I can't feel anything bad in 1st, but you can still hear it.

I'm wondering if I should even start a new tune with it the way it is. 1st still rolls fine and doesn't surge or anything and 2nd-5th are fine. I can still run WOT in 3rd to redline if I want/need to. I'd just hate to have it pop in the middle of a tune.

Just a little update. It's been over 100 miles and she's still kickin. I changed the rear diff for the first time(48K) a couple days ago and I think there was more metal in there than there was in the tranny. Everything feels a little smother with all new fluids. It's still whining on acceloration and deceloration in 1st gear, but you can't feel any clunks or grinding and the rest of the gear are fine.

 

1st still feels strong when you give it half pedal after it's rolling. I'm just having a hard time ripping it apart when it's still drivable. Over the last 20 years I've burned up a lot of automatic tranny's and blew quite a few manuals, but this one is different from any in the past. I usually comlpetely shell the gear and it's usually second that shatters or something gets bent and you just know it's pretty much done, but this one is different.

 

I still think I'm going to drive it till it dies. I'm going to start collecting the parts I'll need for the re-build so I'll have them on hand when it blows. So take a guess at how long she'll hold out for me.

3,452 miles.

O.K. This happened at 48,193 miles and I am now at 48,341 miles. I'm having a hard time not stomping it in fist just to see if it will hold. I'll try to get some video so you guys can hear what it is doing.

I'll say either until your clutch fails (and you'll fix it then to save $$$) or about your 3rd run at the track.

The 1st one you'll go, but not real hard out of 'fear'.

The 2nd one will go harder, but not all out due to increased confidence.

The 3rd one will handgrenade due to saying "what the hell...." and wanting to show the car can still get down the track fast....

4,375 according to my mathmatical equasion.

I just did the clutch last Sept. Replaced it with a SPEC Stg2 clutch and LWFW. The clutch is holding fine and may have contributed to the gear chip since the stock clutch would have slipped a little at that point. There is no slip at all with this clutch after it engages. I'm trying not to even drive it to the track because I know I would be tempted to run it once I got there. I'd say three runs is about what it's got left in it.

That's how I finished off the stock clutch last year. First run it slipped a little in 1st. Second run slipped in 1st and 2nd. Third run slipped in 1st and there was nothing when I went to 2nd and nothing in 3rd. I ended up grabbing 4th for a trap speed of 48MPH:lol:. After that, I let it set for 1/2 hour and drove it 40 miles home. I already had the new clutch and LWFW sitting on the shelf so I only had 2 days of downtime for the clutch. This time it will porbably be down a little longer than that.

 

I'll change the fliud in the tranny again(after 200 miles) tomorrow to see if any more metal comes out.

4,375 according to my mathmatical equasion.

you must've used a different correlation than me...

ur prolly right

A month later. How's your tranny holdin' up quicksilver? Serviced it yet?

She's still holding together so far. I've even floored it in 1st gear a few times after the clutch is engaged and it doesn't give any bad feedback through the stick. It's getting a little louder in first, but the rest of the gears are o.k. I've been working on a new tune, so I've done at least 30 WOT logging runs in 3rd with no problems so far.

I'm aiming for Aug/Sept for the rebuild. I'm trying to hold off as long as possible so I can afford a better gearset, but the price of the PPG gears just went up from $3800 to $4300 this week so I now need another $500 just for parts:mad:! I may just re-build this tranny to stock on the cheap and get another case and do the high dollar build over the winter.

It's hard waiting to re-build it since I have the new 20g sitting in my room and I shouldn't really install it until the tranny is fixed.

Ouch, that sounds expensive. Wouldn't it be cheaper to find somewhere a used manual gearbox altogether, swap it out and call it a day? Or do you have to beef it up anyway to hold your mods?

I've looked for a used tranny, but most people want about $2k for a used one. I can get mine re-built to stock for that. I want to make the "spare" basically bullet proof, but it'll cost me. I really do plan to drag race and do the road course next year, so I really do need to beef it up. If I jacked 1st out of the hole on stage 2 image what I could do with another 100HP:).