Defender gearbox in a series 3???

[leaf sprung]

I have been trying to find an overdrive for my series 2a for ages but they seem to go for loads of money on ebay.

As an alternative - does anyone know if a standard 5-speed defender/90 'box will go in? Basic engine casting looks the same, so maybe?

Bonus would be higher road gearing with a fith gear.

I'd be really grateful for your help.

Cheers.

[SmokinV8]

Cant be that difficult to find one surely?? I just sold a fairy overdrive from my series 3 for £100! Usually a few around, ebay not the place to look as way too high. Get yourself along to a land rover show where they have a spares sort out as well.

[funk odyssey]

don't bother with an overdrive unless there is evidence that it's been rebuilt - they are regularly abused by people using them as splitter boxes.

once they break - the parts are v expensive.

A far better option IMHO is to buy a high ratio transfer box kit from Ashcrofts or someone like that - this raises your higher ratios but leaves the low ratios untouched

[mwy1964]

I think you may have a challenge other than just fitting the gearbox.. The Series is part time four wheel drive. The Defender box is full time and the front axle has CV joints in to cope, where as the Series axle has plain old UJs.. I also think the Defender box is longer and mounts are different...

The options available are:-
Ashcroft upgrade for Transfer box
Overdrive
Bigger tyres
Or fit Disco or Rangie 10 spline diffs

[funk odyssey]

actually don't underestimate the bigger tyres option

I put 750's on my SWB diesel and hardly ever used the overdrive as the new tyres raised the gearing so much

[leaf sprung]

Has anyoe tried Discovery differentials in a series vehicle? Do the existing half shafts fit these diffs please?

[mwy1964]

I think early Discoverys had 10 spline diffs with the changeover from 10 - 24 spline being 1998 (If my my memory is correct)...

Its 10 spline diffs you will need if you have an 88" Series... Different situation if you have a 109 as I think these had salisbury rear axles and the Rangie diffs do not fit(Need to check as never had a LWB and only reciting what I think I have read over time)

[leaf sprung]

Cheers for all your help. I have an '88 and I think I'll try the uprated diff option first.

[mwy1964]

leaf sprung said:

Cheers for all your help. I have an '88 and I think I'll try the uprated diff option first.

Yep agree...

Then a 200TDI, from a Discovery, as an engine transplant