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DISCUSSION => Engine + Driveline => Topic started by: cheesebox on December 14, 2007, 06:39:52 AM

Title: Making transmission feel new again
Post by: cheesebox on December 14, 2007, 06:39:52 AM

Guys, what would be your suggestsions for improving the general feel of the transmission, getting rid of slack and getting it as close as possible to that taut feeling it would have had when it came out of the factory?

I'm talking about the slack you notice if you go off/on/off/on on the throttle. Not that I do that very often, but that gives you an idea of what I'm talking about! Basically I've noticed my car jolts more than it used to.

So, what would you replace, and in what order of importance?

I can feel a project coming on!

Cheers all...

Title: Making transmission feel new again
Post by: Febi Guibo on December 14, 2007, 12:57:16 PM

oh jeez... tranny mounts, guibo, prolly motor mounts and diff mounts while you're at it. I suppose while yer down there, a new CSB too!

are you talking about the tranny, or also the shifter?

Title: me too
Post by: ScreamerBeemer on December 14, 2007, 01:42:54 PM

I have that same play going on. If you grab the driveshaft and try to turn it while in gear there is a good bit of play there.:confused:

Title: Making transmission feel new again
Post by: gearheadE30 on December 14, 2007, 04:12:02 PM

It's called drivetrain lash, and a little bit is normal. Manual transmission cars feel it more than autos because the torque converter smooths it all out. Since gears can't be zero-tolerace, there is a bit of movement between each pair of gears. If you think of how many sets of gears there are in the tranny and diff, you get a lot of play. New drivetrain mounts and bushings are about the only way to get rid of any of it. Of course, the engine and tranny mounts will significantly increase NVH.

Title: Making transmission feel new again
Post by: cheesebox on December 15, 2007, 12:23:41 PM

Thanks for the info. I've not had any of the drivetrain apart, so I'm not familiar with much of it. Previously I had no idea what guibos, NVH and CSB were - have done a bit of background reading and feel a lot more knowledgeable.

Now I think I know what was causing some unusual noises in my previous car...

I think I'll start with the mounts, and maybe move onto the bushings later - replacing these sounds a bit more involved.

Thanks guys!

Title: Making transmission feel new again
Post by: D. Clay on December 16, 2007, 12:06:16 AM

I had my car on a lift one day and twisted the driveshaft. There was a good bit of play in the differential.  I replaced the differential with one that had 100,000 miles instead of 200,000 and it removed about half of it. I've sort of learned to drive around it. Second gear is the worst.