..overdrive for 05 td5 90 csw

..anyone here done this....please
..i've had a quick look online at a gkn conversion...
..is it worth the hastle...or is it a simple waste of time...?

I'm finding that I need to do more motorway work...and the noise after a few hours is starting to do my head in! ....don't really want to chop it in for a disco or RR....

How much is the gkn conversion?

A cheaper option might be to swap the transfer box for a disco one - 1.222:1 high ratio then instead of 1.410:1 That and fit some 235/85/16 tyres (always assuming you've not done that already) and it'd be a fine motorway burner

agree. an 05td5 would have came with 235/85/16 tyres unless you didn't opt for the alloy rims, but steel rims instead.

gkn over drive will be abt 1k pounds without installation with the disco or 1.222 or q gear upgrade will be abt that price too.

the new 2007 defenders are 1.222 ratio geared.

pros for gkn, you get an extra top speed gear with 18% increase in ratio. easy to install as it's just a bolt into the PTO mount.
cons for gkn, you have to switch the overdrive on and off. it's electronic linked, if you happen to keep dunking the fella into water, it's not going to like it very much.

pros for 1.222, you get an overall increase across all 5 gears in hi ratio by abt 11 to 15%, can't remember. check the ashcroft transmission site.
cons for it, you need to drop the transfer box which can be a scary thing if your vehicle is still under warranty. if you fail to put the thing back properly, it can start leaking.... terribly.