Lotus Elan and Lotus Elan Plus 2 Forums

Doh! I didn't realize the brace was bolted to the housing too. That changes the type of force it can resist by a bunch.

Which ear breaks off normally? If it's the lefthand one, it's the driveshaft torque causing it. If it's the righthand one, it's the open diff. I've been really gentle on the driveline especially now that the donuts are gone. No burnouts.

Kieth----found a sliding spline shaft from a TRiumph GT ---they look suspiciously like the sliding splines in my ?lan -- -- ed

Ed!! Glad to hear from you again. You had me worried since you've been silent for the last few days.

Sliding splines are something I've never seen. Ho help here. Sorry.

you can see one in my pic section Ive posted my chassis there ----its a tube with universals at each end and the tube slides in a spline at the end ----used on 26rs --the pic was on disassembly -- apologies for the grotty condition of the chassis ---its much nicer now [been busy trying to figure out the thermal inversion posts for the last week ]- -ed

Keith

I have seen 2 or 3 broken diffs over the years and cant remember any systematic pattern. I broke the top right hand side bolt once ( discovered it via the same clunking sound as you) so tension loads on overrun on this side are not insignificant or maybe I just drive to hard in reverse !

Rohan

Now that I've pondered the way those ears are loaded the brace seems a reasonable approach to solve it. Can't argue with a successful solution.

Just wonder if there is another way that is less of a problem to install. Seems to me the way to go is to restrain the rotation of the diff housing by applying a 5_DOF thingie to the bottom of the diff and the lower chassis.

The rotation about the halfshafts is already overconstrained with four mounts when three will do it. Using just the two top mounts to resist the driveline torque seems silly. The forces on them and the ears could be halved with another simple mount on the bottom.

The diff brace is not that difficult to install. It helps of course if you already have the rear suspension in bits If you were to install the diff brace while changing the driveshafts or rear dampers the extra effort involved is minimal.