01 Boxster Base: Grinds on 3rd gear shift over 5K RPM

[Ericwalsh1982]

Hi all, I'm new to the forum, just picked up a great deal. '01 Boxster base with 39,000 miles in super mint condition. I had a Service Consultant at my local Porsche dealer drive the car and he thought everything seemed great.

All the shifts are super smooth, EXCEPT when shifting up from 2nd to 3rd gear over 5000 RPM, it seems to catch and grind each time. I'm not sure if I'm doing something wrong shifting my new toy or if there could be something more serious.

Any ideas, comments or experiences would be welcomed. Thanks in advance...

-Eric

[jdlmodelt]

why are you shifting between gears while your engine is rev'ing at 5,000 RPM?

[SJEFFB986]

Yes, 5k rpms sounds way to high between 2nd and 3rd gear gears! 3,500 maybe 4,000 rpms is ideal! My .02 cents.

[crooster]

Things I would check:

- front motor mount. If this has never been changed its likely that the rubber bushing is failing. If you notice a lot of shifter movement when getting off the throttle suddenly then this probably needs replacement. Mine had partially failed.
- bleed clutch hydraulics. Any air in system might cause the clutch to not fully disengage. Might as well replace all the brake fluid at the same time. Porsche recommends every 2 years.
- drain transaxle oil and check for any metal debris. Perhaps a synchro is failing? Good idea to chage the oil anyway if you don't know when it was last done.

[Ericwalsh1982]

I'm shifting at high RPM because I'm driving fast and enjoying the fact that I have a Porsche. I don't push it all the time, but when opportunities present themselves, like on ramps, I like to really drive it.

Crooster, thanks for the helpful input. I have absolutely no problems shifting below 4000 RPM, the shifter is silky smooth and I'd never even know something was amiss if I was just driving it like a hyundai. I'll take it in and have those items looked at as you recommend, but does the fact that it's perfect all other times except when shifting from 2nd to 3rd at high RPM change any possibilities in your mind?

[BIGJake111]

They car doesn't rev to 7 for it all to not be utilized. That's like telling someone with an s2k to always short shift.

[JayG]

Originally Posted by SJEFFB986

Yes, 5k rpms sounds way to high between 2nd and 3rd gear gears! 3,500 maybe 4,000 rpms is ideal! My .02 cents.

HUH????

Look at HP/torgue curve on the engine. Lots of power over 4k

On the 3.2, HP peaks around 6200 rpm and torque around 4700 rpm with a stock motor

in any case, it should not matter what gear you up-shift from, they all should be good to 7000

[thstone]

You should be able to shift at any RPM up to redline in each gear without any grinding.

With that said, there could be any number of issues causing the symptoms that you describe.

Be sure that you're getting the clutch all of the way in and not hammering the gear shift. But you shouldn't have to baby it or shift extra slowly either.

With that being said, it sounds like your 3rd gear synchro is being problematic.

Start with the three items that Crooster mentioned: Check your front motor mount, check the clutch hydraulics, and change the transaxle oil (using the expensive factory oil for the refill). The only other thing I would add is to have your mechanic check the shift cable adjustment.

If nothing comes up amiss, then its most likely the synchro. You can either pull the trans and have it repaired or swap in a used trans.

It is generally cheaper to swap in a replacement as they are typically available for around $500 and the parts + labor to repair your existing trans is likely to be more than that. (00 01 02 03 04 Porsche Boxster 2 7L 2 7 5 Speed Manual Transmission 19 037 Miles | eBay

I had the exact same problem with my 3rd gear synchro and swapped the trans myself after buying a used trans from another member here on the Forum. Should take a typical DIY'er 8-10 hours. Its not technically difficult but rather just a lot of stuff to remove and re-install.

Good luck and let us know what you find.

[jdlmodelt]

I guess I'm the only one in this group that doesn't speed shift. Are you telling me you don't take your foot off the throttle when you depress the clutch pedal to change gears? No wonder clutches wear down in 50k miles.

I do enjoy driving mine hard from time to time but I still don't speed shift. I bought mine to last me a while.

[Porsche9]

I just had a similar problem shifting from 1st to 2nd. It ended up being the motor mount that caused the problem. The rubber goes bad on these things with age. Start with the easy stuff the other guys described first. The syncro is the last thing on the list of possibles with the gear oil change (should do this anyways if it has not been done in the last few years) easily telling you if this is the issue. Good luck.

[More]

It could be a Syncro or a gear tooth. Either way it's a very expensive fix. Be prepared to part with some $$$

[shadrach74]

Originally Posted by SJEFFB986

Yes, 5k rpms sounds way to high between 2nd and 3rd gear gears! 3,500 maybe 4,000 rpms is ideal! My .02 cents.

Why is 5000 way too high and why is 3500 to 4000 ideal?

Originally Posted by jdlmodelt

I guess I'm the only one in this group that doesn't speed shift. Are you telling me you don't take your foot off the throttle when you depress the clutch pedal to change gears? No wonder clutches wear down in 50k miles.

I do enjoy driving mine hard from time to time but I still don't speed shift. I bought mine to last me a while.

No one said anything about speed shifting... The OP was clearly talking about executing an up shift from second to third above 5000 RPM.

[crooster]

Speed shifting = I really have no idea how to drive a manual transmission, IMO. Unless you are driving a GT3 Cup with a sequential shifter you should be lifting off the throttle when upshifting.

[Ericwalsh1982]

thank you for all the great advice, I'm glad to be a part of this community. I am taking it in this week to start manual transmission fluid flush and transaxle and will also have motor mounts checked. I'll keep updates coming.

[jdlmodelt]

Originally Posted by crooster

Speed shifting = I really have no idea how to drive a manual transmission, IMO. Unless you are driving a GT3 Cup with a sequential shifter you should be lifting off the throttle when upshifting.

I'm with Crooster. I wasn't raised to shift with the engine rev'd. We needed our farm equipment to last a LONG time. I treat my Boxster the same way.

[Krieger]

Porsche did make farm equipment.

[kk2002s]

WOW did this thread ever go sideways.
Do you get grind/issues shifting at lower RPMs?
Where is your clutch pedal engaging (Bottom-Floor, middle, top) should be middle-ish
You can do as mentioned Fluid changes, front motor mount. This would not be a waste of time as mounts typically need replacing anyways and fluid changes (trans & clutch) are just good maintenance.
There are also (2) trans mounts. I believe they are filled with fluid so when they go bad they tend to leak

I'm not familiar with the shift cables but could that contribute any way?

Welcome

[Ericwalsh1982]

I don't have any shift problems in any other gears or at lower RPMs at all. Silky smooth all other times.

Clutch engages low to middle

I'm wondering if it is just a bad 3rd gear synchro, but the car only has 39K miles on it and was babied so I'd be really surprised if this went bad already.

[BIGJake111]

Have you tried double clutching Alfa Romeo style?

[biglimited]

Same trouble here with 3rd, but not all times fortunately... Mine is 95000km driven, near mintcondition too. I going to try changing transmission oils first..