overdrive for ex army Series III

In article , snipped-for-privacy@slinnings.com (Rune Slinning) growled:

I had one in my 88" SIII. I found the problem with it was that it takes very little oil, so if the gaskets leak even a little bit then it runs out of oil really fast, so it goes bang and you end up re-building it (I have various bits on my mantlepiece as souvenirs ;-)). So if you do find one 2nd hand (I don't believe they're available new any more for Series boxes) then do take care of it and check the oil level often.

An alternative you might like to consider to make your landie more long legged is to change the ratios on the diffs. My SIII had previously had this done and it made a big difference. It means you can get quite so much pull in low box, but it's worth it for the difference it makes on the road.

I think it's also possible to get new gears for the transfer box to achieve the same effect, but this is more work to do.

Thanks for the advise? Where do I start looking for diffs? How can I find the ratio on the current diffs?

Rune

(Rune

You can get new ones. One of the chassis companies supply them as part of a package (chassis, parabolics & overdrive). It might be a Rocky Mountain unit. You can also get higher ratio transfer boxes which are the same ratio as an overdrive but without the extra gear lever. Jon

In article , snipped-for-privacy@slinnings.com (Rune Slinning) growled:

ITYM "advice" ;-)

I think mine came out of a Range Rover.

Jack one rear wheel up. Rotate the wheel once and count how many times the prop shaft goes round. Then multiply that figure by two. I think that's right, we've just been arguing where it's multiply or divide! Anyway typical ratios are 1:3.5 or 1:4.7 so if x2 is way different to that then divide by 2 instead ;-)

yes, you multiply it by 2. when only one wheel is in the air, the prop-shaft will only rotate half as much as if both wheels were rotating in the same direction (due to the differentials as i'm sure you are all aware).