Gearbox issues?

[Mr Plums]

Hi, i have recently had a 2nd hand box fitted which I purchased off a member on here which supposedly had no problems.

However, at high revs at speed I get crunching and not going into 3rd gear smoothly at speed.

I have put the gear stick in every gear position and wiggled it side to side with the ignition off, and it's got the springy feel equal at both ends apart from 3rd gear. In 3rd, its springy when you move it to the left, but when you move it to the right, theres a dead feeling like somethings worn, it doesn't move much to the right when in 3rd gear with no springy feel.

Also when i shift from 4th to 3rd gear, the gearstick moves up and right slightly like its going into 5th, but 5th is even further over to the right.

All gears are good while driving normal, but 2nd to 3rd crunches, it just doesn't feel right.

Any suggestions?

 

[NorthloopCup]

Check the linkage adjustment and also check it wasn't damaged in anyway when you clobbered the kerb a few weeks back. Check all the mounts as well for any excessive play. You never know it could be something simple or it could be internal.

 

[Mr Plums]

Its not when I hit the curb mate, I noticed it a couple of days after I had it fitted, ill check the linkage etc too, f**king hate these gbox's!

I'm going for solid engine and box mounts too when I get off my hols, if its fucked ill get it refurbed and done properly, cant be arsed with 2nd hand boxes, you never know if they're going to be right

 

[NorthloopCup]

Its not when I hit the curb mate, I noticed it a couple of days after I had it fitted, ill check the linkage etc too, f**king hate these gbox's! 😧

I'm going for solid engine and box mounts too when I get off my hols, if its fucked ill get it refurbed and done properly, cant be arsed with 2nd hand boxes, you never know if they're going to be right 😧

I was trying to be optimistic mate. You still got your original gearbox? Or was that removed and left at clioturbo?

 

[Mr Plums]

I was trying to be optimistic mate. You still got your original gearbox? Or was that removed and left at clioturbo?

Yes thanks mate, it was left at clioturbo, I didn't think it would be worth selling, I wish I would have kept it now for spare parts

I just want a good nice smooth gearbox, its doing my head in now dude

 

[NorthloopCup]

Yes thanks mate, it was left at clioturbo, I didn't think I would be worth selling, I wish I would have kept it now for spare parts 😧

I just want a good nice smooth gearbox, its doing my head in now dude 😧

I could've refurbed your original one for you as well!

 

[Mr Plums]

I could've refurbed your original one for you as well!

What sort of price would you charge for a rebuild mate?

 

[NorthloopCup]

What sort of price would you charge for a rebuild mate?

All depends on what it needs replacing mate really. Difficult to say until you open it up and have a nosey around.

 

[Mr Plums]

All depends on what it needs replacing mate really. Difficult to say until you open it up and have a nosey around.

How long would you need it for?

Do you have any box's in to swap parts over? Or would you recommend new parts?

 

[NorthloopCup]

How long would you need it for?

Do you have any box's in to swap parts over? Or would you recommend new parts?

Well it all comes down to what parts it needs. Some of the stuff my box needed wasn't on the shelf so I had a 10 day lead time.
I do have some spare parts from boxes I've stripped, but if your going to the expense of getting the box out, you want to go with new parts imo.

 

[Mr Plums]

I went for a drive earlier to test the box.

It drives brilliantly in every gear, every gear change is smooth while driving normal with a bit of spirited driving

The only time the box crunches or feels notchy, is over 6k revs when you rush the gear change from 2nd to 3rd.

If you thrash it in 1st to 2nd and then 2nd to 3rd and wait 0.5 secs, the gear change is fine.

If you thrash it from 2nd to 3rd under 6k revs its 90% fine, its when I thrash it from 2nd to 3rd over 6k revs, it feels like i beat the gear as to speak.

Any more ideas?

 

[NorthloopCup]

I went for a drive earlier to test the box.

It drives brilliantly in every gear, every gear change is smooth while driving normal with a bit of spirited driving

The only time the box crunches or feels notchy, is over 6k revs when you rush the gear change from 2nd to 3rd.

If you thrash it in 1st to 2nd and then 2nd to 3rd and wait 0.5 secs, the gear change is fine.

If you thrash it from 2nd to 3rd under 6k revs its 90% fine, its when I thrash it from 2nd to 3rd over 6k revs, it feels like i beat the gear as to speak.

Any more ideas?

Dog teeth on the gear and selector ring worn mate. My old cup box was the same in 3rd gear, but on downshifts. What oil is it running on?

 

[Mr Plums]

Dog teeth on the gear and selector ring worn mate. My old cup box was the same in 3rd gear, but on downshifts. What oil is it running on?

I'm not sure mate, Andy am@ct sorted it all, is this a common problem?

Is it rebuild time? Its a shame mate because other than this it feels like a good box funnily enough.

 

[NorthloopCup]

I'm not sure mate, Andy am@ct sorted it all, is this a common problem?

Is it rebuild time? Its a shame mate because other than this it feels like a good box funnily enough.

It could be that the oil is a bit to slippery for the gears/synchros. It's pointing towards rebuild time though if I'm honest though.

 

[Mr Plums]

It could be that the oil is a bit to slippery for the gears/synchros. It's pointing towards rebuild time though if I'm honest though.

What gbox oil do you recommend mate?

I'll change the oil, get solid mounts, adjust the linkage, if that doesn't do it ill get the box refurbed, I want new mounts anyway so I wont be getting them for nothing.

 

[NorthloopCup]

What gbox oil do you recommend mate?

I'll change the oil, get solid mounts, adjust the linkage, if that doesn't do it ill get the box refurbed, I want new mounts anyway so I wont be getting them for nothing.

Just use the Renault stuff mate. It's cheap enough not to worry about if it doesn't fix the problem.

 

[NorthloopCup]

@MrTom my usual gear oil preference is redline mtl, but at £60+ to fill the box, your not gonna be too chuffed if it still crunches on gearchanges!

I ran mtl in my straight cut Quaife box that was coupled up to a 2bar boost motor. A good few 160mph+ runs and trips to the ring meant it was time for a winter inspection. It was like brand new, literally not a sign of anything getting hammered under heavy loads at all. From that point on it was my oil of choice for stressed transmission and it will also be running in my cup box.

 

[sburrell93]

It could be that the oil is a bit to slippery for the gears/synchros. It's pointing towards rebuild time though if I'm honest though.

Out of interest, how long is a box in this kind of condition likely to last before it's basically fucked? (fully expecting the 'how long is a piece of string' reply lol).

 

[NorthloopCup]

Out of interest, how long is a box in this kind of condition likely to last before it's basically fucked? (fully expecting the 'how long is a piece of string' reply lol).

Driven sensibly it could last years mate. Driven like a racing legend I'd say weeks. It's all about having a bit of mechanical sympathy tbh. If most people could see what the gearbox was trying to do when they selected each gear, they'd hopefully be able to understand the loads that it's put under and use mechanical sympathy from there on.

 

[sburrell93]

Driven sensibly it could last years mate. Driven like a racing legend I'd say weeks. It's all about having a bit of mechanical sympathy tbh. If most people could see what the gearbox was trying to do when they selected each gear, they'd hopefully be able to understand the loads that it's put under and use mechanical sympathy from there on.

Ah, well, it's pretty much seeing track use only at the moment...lol! I do try and give it a bit of time between changes though and not just slam it in, but in that case if it lasts me the rest of the track days I do this year I'll be happy. Maybe get my old one refurbed and swap it over winter.

 

[NorthloopCup]

Ah, well, it's pretty much seeing track use only at the moment...lol! I do try and give it a bit of time between changes though and not just slam it in, but in that case if it lasts me the rest of the track days I do this year I'll be happy. Maybe get my old one refurbed and swap it over winter.

Is it crunching now? If it's not you'll more than likely see your season out tbf quite easily.

 

[sburrell93]

Is it crunching now? If it's not you'll more than likely see your season out tbf quite easily.

Yeah it is mate, very similar to Tom's above. Crunches when rushed into 3rd at high revs.

 

[NorthloopCup]

Yeah it is mate, very similar to Tom's above. Crunches when rushed into 3rd at high revs.

Ah right. Same items fucked then I'd say.