Todd 13 Posted November 28, 2019 Recent gearbox swap from toploader to a c4 with 3k stalkier in a xy Once hitting around 85kph and over I get a surging vibration ,during swap I had new tail shaft balanced with new uni’s ect. i’m having Tail shaft re checked tomorrow but i thinking it’s going to be something more deep then tailshaft anyone had anything similar with this transmission swap. Share this post Link to post Share on other sites
SPArKy_Dave 8,871 Posted November 28, 2019 From memory that exact type of vibration, is often caused by an out of balance torque converter. I'd try another torque converter, tbh. Another possibility, is a mismatched crankshaft harmonic balancer - can occur if the original flywheel, crankshaft and front balancer, were originally balanced as a matching set. Share this post Link to post Share on other sites
bear351c 10,270 Posted November 29, 2019 Just chasing this very thing in the XB..... Have you checked pinion angle? Rear trans mount? Jury still out, on mine. Still at the workshop... Share this post Link to post Share on other sites
Todd 13 Posted November 29, 2019 It’s turns out I got lucky for once and tailshaft was out of balance at high speed so re balanced seems all fine so far.hope bear you get a solution soon champ 2 gerg and bear351c reacted to this Share this post Link to post Share on other sites
Todd 13 Posted December 1, 2019 Dam it I jumped the gun it still vibrates on highway cruising at 2600rpm and above, also feel a lighter vibration in park in same rpm range and above talking to gearbox builder and he believes the Clevo most likely balanced to previous toploader. were are considered adding some weight to flex plate and observing it gets better or worse without pulling c4 out yet 1 bear351c reacted to this Share this post Link to post Share on other sites
bear351c 10,270 Posted December 1, 2019 Mine may be the rear bearing in the extension housing, gotta wait until Monday...... Share this post Link to post Share on other sites