lexi Posted February 6, 2013 Share Posted February 6, 2013 I have a series gearbox that I may build as a spare. It is a ser 3 B suffix. What parts and numbers would be needed to take that box to suffix D? Is it worth the upgrading? Quote Link to comment Share on other sites More sharing options...
Snagger Posted February 6, 2013 Share Posted February 6, 2013 The lay shaft, input pinion, layshaft drive gear, third gear, 3rd/4th synchro are all different. I think the reverse idler gear and its shaft are also different and I suspect they might not compatible with the casing (that's certainly true of suffix A). It's a lot to change unless the existing parts are all scrap. Quote Link to comment Share on other sites More sharing options...
lexi Posted February 6, 2013 Author Share Posted February 6, 2013 Thanks Nick. It is a lot. Quote Link to comment Share on other sites More sharing options...
Phil Hancock Posted February 6, 2013 Share Posted February 6, 2013 Reverse gear and shaft are the same B to D, but you will also need 1st gear, 2nd gear, 1st/2nd syncro, 1st/2nd selector rail & layshaft. Quote Link to comment Share on other sites More sharing options...
lexi Posted February 6, 2013 Author Share Posted February 6, 2013 Cheers Phil. I will see what bits can be obtained, versus the condition of this box when stripped. Quote Link to comment Share on other sites More sharing options...
secondjeremy Posted February 7, 2013 Share Posted February 7, 2013 Suffix D is significantly different - the main difference being the 'coffin-shaped' engagement teeth which are unique to that box. Quote Link to comment Share on other sites More sharing options...
Snagger Posted February 7, 2013 Share Posted February 7, 2013 There isn't a great deal of difference between the units operationally. I have read many times that the D and later units are stronger, but I don't see why - they use the same bearings and bushes and seem to have very little differences in the gears and synchros, just detail differences that make them incompatible with each other. Obviously, the changes were made for a reason, and the 3rd/4th engagement teeth will be better at preventing a box from jumping out of gear, but the only clear major enhancement is the reverse idler and shaft. Ironically, my Suffix E (factory rebuild) is an A unit with D main and lay shaft components, but the A case can't take the later reverse parts, so it still has the weaker idler bushing rather than bearings. Quote Link to comment Share on other sites More sharing options...
Phil Hancock Posted February 7, 2013 Share Posted February 7, 2013 The only benefit is the ECM gears are more resistant to jumping out of gear. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.