Hard to select gears

[Maidens1979]

I was on track at Croft last weekend I noticed that when I was changing up gear 2nd to 3rd, 3rd to 4th at around max revs the gear change felt difficult to select, no crunch no noise just a feeling of resistance.
Anyone got any ideas on what could be causing this?

 

[Frank Perry]

I get the same thing - I think it's syncro issue but not 100% certain. Only from 2nd to 3rd for me... Which makes me think it's syncros as they are renowned for failing.

Perhaps someone else may have a better explanation but ultimately, put up with it, replace the box or have your box refurbed are the only options I believe...

 

[Maidens1979]

To add a little more info to my situation, the gearbox is perfectly fine when not changing up at high rpm, and the issue only arises when I’ve been either driving hard on the road for a while or say three hard laps on track.
Could it be gearbox oil not being good enough quality for this kind of driving?

 

[RSRowe]

A fluid change, and bleeding the clutch up may help.
But ultimately it’s just borrowed time as Frank says.

 

[VeiRoNv2]

I had crunch in 3rd and 4th so I tried changing to a good oil as it had very good reviews on the forum and after some driving haven't had any issues since,I do try to be careful generally anyway considering the chocolate gearbox,and this is with the ZPO too.

RED LINE MTL 75W80 75W-80 GL-4 Gear Oil Manual Transmission 1 US Quart 0.946 L 83522502092 | eBay

SAE Viscosity: 75W80. SAE 80 / 80W / 75W80. The secret to their success is two-fold. First, they have the appropriate coefficient of friction for most manual transmission synchronizers. Secondly, the viscosity characteristics of MTL and MT-90 allow proper shifting over the entire temperature...

www.ebay.co.uk

 

[pepinosport]

I had resistance trying to engage 6th and downshifting into 2nd with some Motul gl5 oil. Swapped back to Elf 75w and did 2 trackdays with no issues at all. Give it a try.

 

[Frank Perry]

I had crunch in 3rd and 4th so I tried changing to a good oil as it had very good reviews on the forum and after some driving haven't had any issues since,I do try to be careful generally anyway considering the chocolate gearbox,and this is with the ZPO too.

RED LINE MTL 75W80 75W-80 GL-4 Gear Oil Manual Transmission 1 US Quart 0.946 L 83522502092 | eBay

SAE Viscosity: 75W80. SAE 80 / 80W / 75W80. The secret to their success is two-fold. First, they have the appropriate coefficient of friction for most manual transmission synchronizers. Secondly, the viscosity characteristics of MTL and MT-90 allow proper shifting over the entire temperature...

www.ebay.co.uk

+ for this stuff! I grabbed 2 bottles, just about enough!

 

[littleg78]

I had the same thing when my engine and gearbox were standard.

I found that the clutch wasn’t fully disengaging at high rpm. I checked by stopping the car, putting it in first gear with the clutch fully depressed, then bringing up to max rpm… the car would start creeping forwards once it got up to about 6k.

I don’t know what root cause of the issue was because I swapped out to a Megane engine and gearbox!

 

[RSRowe]

I wouldn't get too focussed on the above.
It's pretty normal behaviour when you're spinning the clutch up that fast. You always get drag in the system.