Crunching Into 3Rd Gear

[mkc2bad]

Hi

I just had my 2000 2.7 boxster in for a full service inc poly belt change and fuel filter as well as the free whell pulley on the alternator being replaced as it was seized. The car was otherwise in perfect condition when I took it in and the gearbox has always been as sweet as a nut. As soon as I got it back and drove it home, there was a crunching sound when selecting 3rd gear, almost as if I haven't pushed the clutch down far enough. Its a sort of metal on metal noise. Its much worse if you shift up at higher rpm, but in general the whole gearbox doesn't feel quite as 'tight' as it did before. Now the garage is saying its nothing to do with them and it is now down to the fact that the syncro is worn and would probably be cheaper to just replace the whole gear box. My real question is, could anything have happeend while it was being serviced to suddenly make my gearbox go all crunchy? All the other gears appear to be fine, and the crunch is much worse when downshifiting from 4th - 3rd.

Thanks

Mike

[JFP in PA]

Consider doing a gear box oil change out, and use the OEM stuff only, a lot of people have had issues after using non OEM lube that went away when they switched back to the factory fill (which has weird specs no one seems to match)...............

[mkc2bad]

Thanks for the tip - Thing is, as far as I am aware, the tranmittion oil has not been changed during the service, so I will def. check and see.

I did a little more inspecting and the crunch happens even when the car is stationary and you put it straight into 3rd (every other gear is fine, except it cruched once or twice when selecting 4th aswell) It's then fine on subsequent shifts as long as you don't pull up the clutch (ie keep foot depressed on clutch and you can select all the gears perfectly) As soon as you pull the clutch up (obviously engaging neutral) and then depress the clutch and try and select 3rd again , the crunch happens. Is this a sign of a worn syncro? It really does feel like the clutch just isn't fully disengaged.

Thanks for all your help :)

Mike

[JFP in PA]

It could be the syncro, only problem is that pulling the gear box to look at it is no small undertaking. Changing the oil is realtively quick and obviously much cheaper, so I'd go that route before pulling the box out. Add in the fact that I've seen this happen when people have used aftermarket gear oils (RP, RedLine, Mobil 1; none of which matches the OEM specs), I think a change out to the OEM fluid is a good starting point. If it still acts up then, you need to pull the box. I noted that someone else had mentioned linkage as a possibility, I've never seen a linkage issue cause a gear to grind, usually if the linkage is off, you can shift it into one or more gears at all..............

[mkc2bad]

It could be the syncro, only problem is that pulling the gear box to look at it is no small undertaking. Changing the oil is realtively quick and obviously much cheaper, so I'd go that route before pulling the box out. Add in the fact that I've seen this happen when people have used aftermarket gear oils (RP, RedLine, Mobil 1; none of which matches the OEM specs), I think a change out to the OEM fluid is a good starting point. If it still acts up then, you need to pull the box. I noted that someone else had mentioned linkage as a possibility, I've never seen a linkage issue cause a gear to grind, usually if the linkage is off, you can shift it into one or more gears at all..............

Thanks very much for the suggestion. I'll get the oil changed out at the weekend hopefully. Just to add...... When the car is stationary it crunches if you put it straight into 3rd..... however if you hold the clutch down for a few seconds and then engage 3rd it shifts perfectly into gear with no crunching. Weird?! Its the same when shifting up from 2nd-3rd - if you hold the clutch in and let the the revs drop right down, it's fine, unfortunatly upshifting from 4th - 3rd still crunches no matter what. I really hope I don't need a whole new box.

Thanks

M.

Edited May 12, 2010 by mkc2bad