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Locked out of 5th gear--what could the problem be?

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Old 04-03-2007, 01:13 PM
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Default Locked out of 5th gear--what could the problem be?

I was driving my 2002 the other day and noticed that out of nowhere I'm being locked out of 5th gear. I can go from any gear to any other gear than 5th. 6th and reverse are both fine. when I try to force it in to 5th, it gets stuck--almost there but not enough. then I have to force it back out of that stuck position to get it free. anyone ever encounter a problem like this? my car has about 51,000 miles on it and to my knowledge, the transmission has never had any repairs other than routine fluid change.

thanks in advance
Old 04-03-2007, 01:35 PM
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Did you grind your gears prior to losing 5th? I use to have bad 1st-2nd grind, which somehow caused me to lose 6th one time immediately after grinding 2nd real hard. Eventually, 6th just came back on it's own. When I lost it a second time a couple months later, I took my car to the dealer. After a tranny rebuild, everything is smooth as silk.

Your 5th gear might come back on it's own eventually. If not, you might want to take it in for service. Regardless, it might be time for a fluid change to see if that helps anything. Good luck bro
Old 04-03-2007, 01:56 PM
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what do you need 5th gear for?

Seriously - that's strange - I hope it works itself back. I agree - start with the fluids.
Old 04-03-2007, 02:32 PM
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Do you skip shift a lot?
Old 04-03-2007, 02:36 PM
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Can you put it in 5th with the engine off and clutch in? How about engine off and clutch out? Try those and report back.
Old 04-03-2007, 10:08 PM
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i have a feeling somethings gone awry in your transmission.

if you skip shift you may have damaged gears...i believe woodwork posted pictures of a skip-shifting transmission.
Old 04-04-2007, 05:36 AM
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As 90crvtec and jyeung528 noted, this sounds like you've destroyed your 5th gear synchro through skip-shifting. Don't try to force it in 5th - you'll only do more damage - to include the shift forks.

When you go from redline in 1st, 2nd (or 3rd) gear, and skip to 5th or 6th, you do an incredible amount of damage to the higher gear's synchros - and this happens many times WITHOUT GRINDING.

The RPM delta between the input shaft speed (9000 RPM at redline in an AP1) to the selected output shaft speed (the gear your shifting up to) is what causes the problem. The upshifting synchro has to slow down the entire mass of the input shaft (including the clutch disc) to match or "synchonize" the throughput speed of the transmission through the gear you intend to shift to (5th in your case). The transmission is not designed to handle this - and you subsequently destroy your synchros in the process. The worst case (and most damaging) would be to shift from 1st (at redline) directly to 6th gear. While not a practical example - it highlights the mechanics involved.

One of the best alternatives to skipping gears is to row through all intermediate gears (with the clutch in) so that each successive synchro can slow the input shaft down to a reasonable RPM, all the way up to your intended gear.

In plain English: from second gear (for instance), put in the clutch and successively move the gear selector through the third and forth gear "gates" prior to selecting 5th - and then re-engage the clutch in 5th. The synchro is doing it's work as you are pushing the gear selector through the "gate".
The only other acceptable option is to double-clutch and rev-match (takes a little more skill).

To the OP:
A rebuild will cost you ~$1400-$2600 for your transmission - depending on how much they have to replace. Ususally they replace a full set of synchros, any forks that are bent, and the gear involved. If there's a lot of metal running through your transmission - you can expect several of the bearings and the oil pump as well.

Give the Hard Top Guy a call. I believe he's got a prestine 2002/03 transmission with around 15,000 miles on it for sale (swapped out for a 2004 trans for the gear ratios). I think it's around $1500 or so. He can also get you an '04 transmission. They're quite a bit more expensive though.

Good luck.
Old 04-04-2007, 05:46 AM
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Originally Posted by raymo19,Apr 3 2007, 04:36 PM
Can you put it in 5th with the engine off and clutch in? How about engine off and clutch out? Try those and report back.
NOT ADVISABLE - AT ALL!
Forcing the transmission into gear with a trashed synchro - even when nothing is running - can damage things to the point the OP won't be able to drive their car at all. Are you going to drive the OP around until his or her car is fixed? For the love of God! Don't make a suggestion unless you know what the hell you're talking about!

BTW: 6th gear will be soon to follow if the OP is not careful.

The transmission will have to be rebuilt or replaced at this point. However, after a well advised gear oil change, the OP should still be able to drive their car - sans 5th gear - until they have their options sorted out.

To the OP: DO NOT ATTEMPT TO SHIFT INTO 5th AGAIN.
Do not skip shift into 6th from any gear below 4th (you're out of choices my friend). When shifting from 4th to 6th, "double clutch" and rev-match to allow the input shaft (and clutch disc) to slow down before attempting to shift into 6th.
Basically, put in the clutch and move the gear sector to neutral, let the clutch out and allow the engine RPM to slow to approximately what it should be for 6th gear, then push in your clutch pedal again and select 6th. It's cumbersome at first - but it's how you'll save your 6th gear synchro at this point and this will give you more options (as in keeping 5 out of 6 gears working) until you figure out what you need to do.
Good luck.
Old 04-04-2007, 07:17 AM
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Originally Posted by slipstream444,Apr 4 2007, 08:46 AM
NOT ADVISABLE - AT ALL!
Forcing the transmission into gear with a trashed synchro - even when nothing is running - can damage things to the point the OP won't be able to drive their car at all. Are you going to drive the OP around until his or her car is fixed? For the love of God! Don't make a suggestion unless you know what the hell you're talking about!
Chill out man! He didn't say to "force" anything. He didn't tell the OP to do anything that the OP probably hasn't already done a hundred times by now(attempting to get into 5th gear, that is).

Regardless, you have clarified the situation and provided some good details/advise.
Old 04-04-2007, 07:38 AM
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Originally Posted by slipstream444,Apr 4 2007, 07:36 AM
...
Don't try to force it in 5th - you'll only do more damage - to include the shift forks.
...
This is not an uncommon problem and the fix will probably be forcing it so forget some advice from those that have no experience with it..

Fifth and sixth share a collar that can get slightly mangled, usually from a failed high rpm shift to third that missed the gate and caught fifth gear.

What has worked for a number of owners is to be persistent using pressure to force engagement of fifth. This is while you are driving as you want a warm box and proper rpm to allow engagement. On my car it took many tries over a two day period and quite a bit of pressure.

Once you get fifth you will also be able to get sixth but engagement will be very rough. Shift repeatedly into fifth and sixth to smooth the rough spots on the collar.

I suggest you change the transmission oil after you get it working to drain and residue that is not picked up by the magnet.


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