Gearbox (synchro?) problems

[adriangwatson]

Hi guys

Wanted to get your thoughts and advice on a gearbox issue I'm having. My car has done just over 30k miles. 2nd gear has started to occasionally pop out of gear and back into neutral. Sometimes this happens when I depress the clutch but it can also happen under load / just cruising in 2nd gear. No other gears have this issue. I'm finding 2nd is also starting to crunch on the gears sometimes too. If I feel like the gear is about to pop out and try to hold the gear lever in 2nd the gears will then start to crunch.

Is this a common issue? Do you think the synchro needs repairing? If so how much am I up for?

Any recommendations for specialist repairers within striking distance of london also appreciated.

Cheers
Adrian

[adsgreen]

Not heard of that one on the RS4 before.

Worth checking the transmission fluid level (long shot).
Possibly the selector forks are broken or possibly one of the engine mounts has failed casing flexing to cause the gear to pop out.

Worth checking any gear linkage adjustment as it might not actually be engaging the gear properly.

To be honest, it's a long shot and most likely you would be looking at a recondition of the gearbox.

[pixsaudisex2]

The Synchro only helps the gear to get to the same speed as the hub. to match them and the hub can then locate correctly onto the gear,
The teeth on the gear are actually what holds it in place (gear).

For second gear to go as you describe its normally from somebody smashing it into second gear or the syncro is fecked causing the teeth on the gear to get worn down. I imagine the gear is worn or any of the reason mentioned in above post can also cause it but you would expect it to also have problems in fourth if it was the cables or mounts. the forks bent worn yes this can also cause problems.

I always use Central Axles in Birmingham for any gearbox problems ( its where most garages go to get them reconditioned. including many many main agents,.)
They are honest and are not rip of merchants they don't see rs4 and charge double like some places..

[sakimano]

Hi guys

Wanted to get your thoughts and advice on a gearbox issue I'm having. My car has done just over 30k miles. 2nd gear has started to occasionally pop out of gear and back into neutral. Sometimes this happens when I depress the clutch but it can also happen under load / just cruising in 2nd gear. No other gears have this issue. I'm finding 2nd is also starting to crunch on the gears sometimes too. If I feel like the gear is about to pop out and try to hold the gear lever in 2nd the gears will then start to crunch.

Is this a common issue? Do you think the synchro needs repairing? If so how much am I up for?

Any recommendations for specialist repairers within striking distance of london also appreciated.

Cheers
Adrian

This is somewhat common in that I've heard it happen to a handful of cars.

Basically the first and second gear synchros are quite beefy but third to sixth are a bit smaller. The one of those four that you use the most is the third gear synchro, and that's the one that breaks down in almost every case.

Full transmission replacement under warranty is what a couple of people had so it's not really been fleshed out as to a repair course for non warranty cars.

JHM were working on a transmission rebuild kit and were redesigning synchros so that we are not beholden to the same design weak points of the stock items. Maybe contact them to see if that's done or for their thoughts on your symptoms? You won't be sending your car there but they're a great resource.

Jake@jhmotorsports.com or v8@jhmotorsports.com

[MikeFish]

He is having problems with 2nd gear not third though.

[esp_mm-270]

When mine went it was more than one gear. Looked at a rebuild iirc was around £3k. I got a used box and amd Essex to switch them, £1200 all in.