Diffs?

Hi all
My k plate 200tdi defender seems very low geared. I can be up to 5th gear in no time at all and anything over 50mph feels like and smells like I'm pushing it.
I rebuilt the truck last year and to be honest did not sort axels or diffs as they were in good order, cooling system is in good order as have just redone it, the owner before me had 33" tyres on there and am wondering if they may have put series diffs on to lower gearing?? Any ideas would be helpfull.

might sounds silly but your not stuck in low range?

No not in low range! That all works as normal

I think I can turn the wheels and count the turns on the diff nose.? I just need to find out how many turns tells me weather it's series or not!
Does anyone have an idea?

you might have a 1.6 ratio xfer box. you can test the diff, see how many turns the wheel does compared to the diff

I see I thought transfer boxes were the same!
Would you care to share some more info on them?

Or which box I should have?

1.6 1.4 1.22

Choices... Fit 3.54:1 difs from a rangie etc. Or fit big tyres. Or fit a 1.2 transfer box. I had the same problem and fitted diffs at £50 each. In my case I had already fitted 1.2 transfer box and could just about get to 65 with engine screaming on 900x16 tyres. I did not want to go faster, just wanted to be able to cruise at that speed with lower engine rpm, which she now does.

Thankyou for help! So a 1.2 box is what I should be putting in? What vehicle would that come from? During the building of my 90 I found out the transfer box was duff and I did swap it out with another one I managed to get hold of, but ratio was unknown to me!

there you go! a 1.2 would be the same ratio as a disco.

Cool so a disco would fit straight on?

Stoopid bladdy forum logged me out mid reply!!! So here goes again... Diffs would perhaps be easiest to do and might well be enough for you. Its getting the balance right. 1.2, 1.4 and 1.6 transfers have the same low ratio. But if you run big tyres and higher ratio diffs, this will affect your low range, gearing it up a bit. Transfer boxes: Stupidly huge tyres. 1.6, big tyres 1.4 and normal tyres or a bit bigger 1.2. It depends what you use the Landy for. Off-road? Motorway miles? All rounder? Personally I would consider changing diffs. You would need to check what you have, 10 spline or 24. Do a search on here, there's loads of info. If you want to theoretically test ratios etc check here: Ashcroft Transmissions - Ratio Calculator

Sorry to keep going on! Lol
Is ther any way visually I can identify the transfer box? I.e stamped numbers etc etc?

There is a sticker that falls off on the back of the box!

My wheels and tyres are 235/85/16 so not stupidly big! I have not personally changed diffs but as above I have done the transfer box! I just need to id it on the landy

To the left of the handbrake drum there should be a sticker which will give you the ratio of the box.
If no longer there? Look at the Ashcroft link I posted - there's a mine of information there that will help you identify it.

Trouble is with old Landys that you never know what a previous owner has changed to facilitate what they needed from the vehicle in their ownership. Series diffs may have been put in yours because of large tyres and mainly off road use.

No sticker unfortunately! Have looked at the link but I have no rev counter so its hard to guess the revs! Would be so much easier if the ratio was stamped on there! All I have is hrc and frc numbers which I'm sure is just casing numbers

Think I will just have a look for a 1.2 t box. Will a discovery 1.2 fit straight on!?