wicked 103 3 Cars Posted August 14, 2018 I have a Xsara 1.9TD BE3R gearbox and can get my hands on fresh 405 BE3 gearbox. I did some math and think the BE3R 1.9TD box with the 3th, 4th and 5th gear of the BE3 would make the box I want. But will the parts of the BE3R and BE3 be interchangeable? I did some searching, but could not find an answer. Share this post Link to post Share on other sites
welshpug 1,626 Posted August 16, 2018 many parts are, those that are not some can be modified to work. main difference is a double set of splines under the 3/4 gear pair on a BE3R, this means the BE3 gear is loose on the BE3R shaft so wont work. the opposite combination can work with the 1st set of splines machined out. the synchro hubs have grooves or the gears have grooves to feed oil, use the right combination here also. small Variances in selectors too, nothing more I can recall, Miles could tell you more im sure. Share this post Link to post Share on other sites
wicked 103 3 Cars Posted August 16, 2018 (edited) Thanks for the detailed info. It is not an easy swap then... The good part: From further investigation, it turns out that I don't need to do the swap. The 405 box seems to have already the same CWP (1:4.03), according to service box, as the 1.9TD box. Did expect it to be 1:4.43 So the gearing of the 405 box is already how I'd like them to be!! It's a low mileage box, so I'll use it as is. Down side that is that it does not have the stronger casing of BE3R, but I'll take that for granted. FYI: The gearing of the 405 SRi box, next to some other boxes plotted below... (in km/h) Currently I'm using the 1.9TD box and like the long gears on high ways, but the gap from 2nd to 3th is a bit too much on mountain roads/tracks. For my new engine I would like to have that a bit shorter, but don't like long 2nd gear from the 1.9 gti box in hairpins either. The upper graph is speed at 6500rpm. Second graph is the speed change through the gear until 6500rpm. I'm still considering to swap the 5th for the 1.9td 5th, make the 5th gear as long as the 1.9TD 5th... Edited August 16, 2018 by wicked 1 Share this post Link to post Share on other sites