Hi All
Bought a Disco 2 recently, very happy with the car. Just have a slight scratching of the gears when changing from 1st to 2nd and 3rd. Seems to be a bit worse the higher the revs. Would it be a synchro problem?

 

to ask the obvious question, have you checked/changed the oil in the gearbox?

 

Just for clarity did you say a 2002 with a manual transmission or do you mean manually moving the automatic gear box gear selector out of drive and through the gears?

 

How did you get a manual tranny

 

I'm assuming since you're asking if it's a syncro problem and that you mentioned manual in the title that you do indeed have a manual transmission..... yes?

Syncros can go out in any gear that has them, generally a downshift would be worse than an upshift and especially common from 2nd>1st gear shifts as that gear is commonly abused. Syncros are not NEEDED for proper shifting if you were double clutching though this is a lot to ask from a typical driver in a daily vehicle. Hell even rev-matching is a lot to ask these days. Your syncros do the job of matching transmission gear speed to they mesh smoothly. Without them you would have to shift into Neutral between each gear and treat it as a pretend gear and then shift into the gear you wanted to go to in the first place. I do this on most every shift in my car to save my Syncros from daily abuse so that I can afford to abuse the hell out of it on the track. You could do this trick if you need to drive your vehicle without synros and not toast your transmission. There's a few tests you can do for finding out if your syncros are burned out and they vary in some cases due to transmission structure so look up some on your vehicle.

To double clutch say from 4th > 3rd, you'll be needing to match the rpm of the transmission, not just the engine which is what rev-matching does. As you know, when you downshift the engine revs will be higher, well the transmission speed needs to match too! The way to speed or slow a transmission is to use Neutral as a gear! When you let the clutch out in neutral, you're actually spinning the transmission along with the engine speed, just not the output shaft and this is just what you need to do.

So here's the operation:
You are driving in 4th gear needing to shift to 3rd.
You will depress the clutch and pull the gear selector to neutral, and then let out the clutch, effectively putting the car in Neutral "gear". Now you can give a quick rev to the engine and transmission since they are connected and speed it up for 3rd gear.
You will depress the clutch and pull the gear selector to 3rd gear and let out the clutch.

If you did this quickly enough and gave the right about of throttle blip input you'll have sped the tranny up while the clutch was out in Neutral "gear" and it will have matched 3rd gears needed RPM.

This takes time to learn, you'll hear it referred to as double clutching, swinging your knee, etc. The reason for the swinging knee is actually because while depressing the brake with the left half of the foot, you blip the throttle with the right half of the foot and your knee ends up swinging right towards the center console. It doesn't mean they are double-clutching really, they are just rev matching or applying throttle to induce over-steer while still braking etc.

I expect by this day an age, youtube can teach the trick. In any case, it'll get you through driving without syncros in a pinch. For me, I don't care much about syncros, this is normal everyday driving I do just out of complete habit. If doing this solves your problem well hey you indeed had syncros that were worn out.

If you have an automatic and I guessed wrong, well then hey interesting info has been added to the forum. LOL

-Greg

 

Thanks Greg, will try this and see

 

Rest of the world gets diesels and manuals

 

Yes, it's a manual tranny

 

We get them in South Africa

 

I actually didn't change the oil yet, planning to in next couple of day's