5th Gear Crunching

[Ryder35]

Hi,

having finally fixed my radiator (leaking) and suspension (leaking) I am getting a problem with the clutch/gearbox. Changing into 5th is fine If I go from 4th to 5th at about 4k revs. Anyhting above that and I get a crunching noise and a resistance to selecting the gear. It will go in but sounds like it is doing some damage.

Any thoughts before I phone RG again?

[LaserTam]

Dont know the answer, but I get a similar problem, when changing into 5th fairly agressively, get the crunching.

[J_S_G]

How many miles are you (both) on? Synchromesh tends to go on 2nd and 5th gears before any others... 2nd because you work through it all the time, and 5th because it's the weakest gear. Anything less than 20k miles, and this shouldn't be happening. Assuming the cars are driven as hard as they should be (once warm!) I'd expect you to likely start spotting this between 25-35k miles; usually at the higher end of that. Definitely something that you'd spot at higher revs rather than lower. (A bit of shonky treatment by a former keeper could have shortened the life there)

If you've got the time/inclination, I'd recommend a quick change of gearbox oil; always helps prolong the life of the oily bits inside.

[Ryder35]

J_S_G said:

How many miles are you (both) on? Synchromesh tends to go on 2nd and 5th gears before any others... 2nd because you work through it all the time, and 5th because it's the weakest gear. Anything less than 20k miles, and this shouldn't be happening. Assuming the cars are driven as hard as they should be (once warm!) I'd expect you to likely start spotting this between 25-35k miles; usually at the higher end of that. Definitely something that you'd spot at higher revs rather than lower. (A bit of shonky treatment by a former keeper could have shortened the life there)

If you've got the time/inclination, I'd recommend a quick change of gearbox oil; always helps prolong the life of the oily bits inside.

Only done 14k, clutch was replaced at 13k. 2nd gear seems fine (touch wood!)

Are we talking big money for a synchromesh problem?

[TVR_owner]

Ryder35 said:

J_S_G said:

How many miles are you (both) on? Synchromesh tends to go on 2nd and 5th gears before any others... 2nd because you work through it all the time, and 5th because it's the weakest gear. Anything less than 20k miles, and this shouldn't be happening. Assuming the cars are driven as hard as they should be (once warm!) I'd expect you to likely start spotting this between 25-35k miles; usually at the higher end of that. Definitely something that you'd spot at higher revs rather than lower. (A bit of shonky treatment by a former keeper could have shortened the life there)

If you've got the time/inclination, I'd recommend a quick change of gearbox oil; always helps prolong the life of the oily bits inside.

Only done 14k, clutch was replaced at 13k. 2nd gear seems fine (touch wood!)

Are we talking big money for a synchromesh problem?

When the clutch was done, the clutch cylinder "should" have been replaced. If it was not, then this maybe the problem. The other possibility is that the clutch adjstment is not correct causing daragging which would give difficulty in gear selection. Both of these would give symtoms in other gears though. Syncro swap will be inexpensive, labour will be the main cost. I suspect if it is synchro, expect a 500GBP bill.

[Ryder35]

TVR_owner said:

Ryder35 said:

J_S_G said:

How many miles are you (both) on? Synchromesh tends to go on 2nd and 5th gears before any others... 2nd because you work through it all the time, and 5th because it's the weakest gear. Anything less than 20k miles, and this shouldn't be happening. Assuming the cars are driven as hard as they should be (once warm!) I'd expect you to likely start spotting this between 25-35k miles; usually at the higher end of that. Definitely something that you'd spot at higher revs rather than lower. (A bit of shonky treatment by a former keeper could have shortened the life there)

If you've got the time/inclination, I'd recommend a quick change of gearbox oil; always helps prolong the life of the oily bits inside.

Only done 14k, clutch was replaced at 13k. 2nd gear seems fine (touch wood!)

Are we talking big money for a synchromesh problem?

When the clutch was done, the clutch cylinder "should" have been replaced. If it was not, then this maybe the problem. The other possibility is that the clutch adjstment is not correct causing daragging which would give difficulty in gear selection. Both of these would give symtoms in other gears though. Syncro swap will be inexpensive, labour will be the main cost. I suspect if it is synchro, expect a 500GBP bill.

Thanks for the info. Slave cylinder was done at the time (august last year)

[J_S_G]

Ryder35 said:

TVR_owner said:

Ryder35 said:

J_S_G said:

How many miles are you (both) on? Synchromesh tends to go on 2nd and 5th gears before any others... 2nd because you work through it all the time, and 5th because it's the weakest gear. Anything less than 20k miles, and this shouldn't be happening. Assuming the cars are driven as hard as they should be (once warm!) I'd expect you to likely start spotting this between 25-35k miles; usually at the higher end of that. Definitely something that you'd spot at higher revs rather than lower. (A bit of shonky treatment by a former keeper could have shortened the life there)

If you've got the time/inclination, I'd recommend a quick change of gearbox oil; always helps prolong the life of the oily bits inside.

Only done 14k, clutch was replaced at 13k. 2nd gear seems fine (touch wood!)

Are we talking big money for a synchromesh problem?

When the clutch was done, the clutch cylinder "should" have been replaced. If it was not, then this maybe the problem. The other possibility is that the clutch adjstment is not correct causing daragging which would give difficulty in gear selection. Both of these would give symtoms in other gears though. Syncro swap will be inexpensive, labour will be the main cost. I suspect if it is synchro, expect a 500GBP bill.

Thanks for the info. Slave cylinder was done at the time (august last year)

Does sound a bit like it dragging, but as TVR_Owner says, you'd get it in all gears.

The synchro on different gears is independent, so you can strip it on one without another being affected. Of course, you'll have lots of nasty bits of metal floating around in the gearbox oil then that have come off it (hence a good reason to change the oil to stop any further wear). The thing with second gear is that people often don't push too hard in first and short-shift into second. I'd give it a try with a 6k+ change-up (once warm!) into second to see if it really is just a 5th problem.

One thing I forgot to mention before... everybody on here seems to use 5th gear before putting it into reverse to stop the "crunch" when wanting to go backwards. I've always thought this is a shockingly bad idea as you're using your weakest gear for that. I'd alternate between 3rd/4th (which get less abuse) for doing this.

Did you buy the car second hand, if you don't mind me asking? 13k before it needed a replacement clutch seems CRIMINALLY short. The slave cylinder seals normally go like clockwork at about 20k, but it shouldn't need any work before that, and I've always had 30k+ out of the clutch plates. Sounds like the drivetrain might not have been shown utmost sympathy in the past, maybe?

Would still just change the oil and see for a bit - tends to improve lots of things doing that. And yeah - a bill for a reconditioned gearbox is ~£1k (there are places that'll do a like-for-like swap to a recon'd one for £750 parts only), so if you can suffer it off the road for a while and have an engineer up to it, then it could work out a fair bit cheaper.

[Ryder35]

J_S_G said:

Ryder35 said:

TVR_owner said:

Ryder35 said:

J_S_G said:

How many miles are you (both) on? Synchromesh tends to go on 2nd and 5th gears before any others... 2nd because you work through it all the time, and 5th because it's the weakest gear. Anything less than 20k miles, and this shouldn't be happening. Assuming the cars are driven as hard as they should be (once warm!) I'd expect you to likely start spotting this between 25-35k miles; usually at the higher end of that. Definitely something that you'd spot at higher revs rather than lower. (A bit of shonky treatment by a former keeper could have shortened the life there)

If you've got the time/inclination, I'd recommend a quick change of gearbox oil; always helps prolong the life of the oily bits inside.

Only done 14k, clutch was replaced at 13k. 2nd gear seems fine (touch wood!)

Are we talking big money for a synchromesh problem?

When the clutch was done, the clutch cylinder "should" have been replaced. If it was not, then this maybe the problem. The other possibility is that the clutch adjstment is not correct causing daragging which would give difficulty in gear selection. Both of these would give symtoms in other gears though. Syncro swap will be inexpensive, labour will be the main cost. I suspect if it is synchro, expect a 500GBP bill.

Thanks for the info. Slave cylinder was done at the time (august last year)

Does sound a bit like it dragging, but as TVR_Owner says, you'd get it in all gears.

The synchro on different gears is independent, so you can strip it on one without another being affected. Of course, you'll have lots of nasty bits of metal floating around in the gearbox oil then that have come off it (hence a good reason to change the oil to stop any further wear). The thing with second gear is that people often don't push too hard in first and short-shift into second. I'd give it a try with a 6k+ change-up (once warm!) into second to see if it really is just a 5th problem.

One thing I forgot to mention before... everybody on here seems to use 5th gear before putting it into reverse to stop the "crunch" when wanting to go backwards. I've always thought this is a shockingly bad idea as you're using your weakest gear for that. I'd alternate between 3rd/4th (which get less abuse) for doing this.

Did you buy the car second hand, if you don't mind me asking? 13k before it needed a replacement clutch seems CRIMINALLY short. The slave cylinder seals normally go like clockwork at about 20k, but it shouldn't need any work before that, and I've always had 30k+ out of the clutch plates. Sounds like the drivetrain might not have been shown utmost sympathy in the past, maybe?

Would still just change the oil and see for a bit - tends to improve lots of things doing that. And yeah - a bill for a reconditioned gearbox is ~£1k (there are places that'll do a like-for-like swap to a recon'd one for £750 parts only), so if you can suffer it off the road for a while and have an engineer up to it, then it could work out a fair bit cheaper.

Thanks for the info. I did buy it second hand and there is a great yooutube vid (that I found after I had bought the car) of it doing standing starts and leaving 30ft of rubber on the ground, so not exactly well treated by a past owner. Fortunately it has a wear and tear warenty for 3 years which was a definate factor in my purchasing decision.