The Rover-Landers of BC

90/110 British Military High
51A Low 1.666 1.41 1.222
3.985 46.834908 23.5020954 19.890729 17.2386318
2.519 29.6053032 14.85615516 12.5733366 10.89689172
1.5074 17.71617072 8.890102536 7.52403636 6.520831512
1 11.7528 5.89764 4.9914 4.32588
0.8314 9.77127792 4.903297896 4.14984996 3.596536632
3.701 43.4971128 21.82716564 18.4731714 16.01008188

90/110 pre' 200TDI High
50A Low 1.666 1.41 1.222
3.585 42.133788 21.1430394 17.894169 15.5082798
2.3008 27.04084224 13.56929011 11.48421312 9.952984704
1.5074 17.71617072 8.890102536 7.52403636 6.520831512
1 11.7528 5.89764 4.9914 4.32588
0.8314 9.77127792 4.903297896 4.14984996 3.596536632
3.701 43.4971128 21.82716564 18.4731714 16.01008188

Disco 200TDI
90/110 200TDI
55A 56A High
Low 1.666 1.41 1.222
3.692 43.3913376 21.77408688 18.4282488 15.97114896
2.132 25.0569696 12.57376848 10.6416648 9.22277616
1.397 16.4186616 8.23900308 6.9729858 6.04325436
1 11.7528 5.89764 4.9914 4.32588
0.77 9.049656 4.5411828 3.843378 3.3309276
3.429 40.3003512 20.22300756 17.1155106 14.83344252

90/100 V8
Disco V8
53A, 57A 60A, 61A High
Low 1.666 1.41 1.222
3.321 39.0310488 19.58606244 16.5764394 14.36624748
2.132 25.0569696 12.57376848 10.6416648 9.22277616
1.397 16.4186616 8.23900308 6.9729858 6.04325436
1 11.7528 5.89764 4.9914 4.32588
0.77 9.049656 4.5411828 3.843378 3.3309276
3.429 40.3003512 20.22300756 17.1155106 14.83344252

I think you'll be happiest with the 200TDI box due to the longer 4/5 split on the highway and a 1.4:1 t. case.

The extra 8% of low first in the military box is the only consideration. You need to decide on a trade off of highway or off road. As we have discussed, I find this a bit low geared with the 1.4:1....

Watch the suffixes with regard to strength. I assume all the 200TDI units are "H".

http://www.ashcroft-transmissions.co.uk/part_1.html#pa1

The LT 77 was introduced to the Landrover range in approx 1983 with the suffix D box and was developed over the years to the suffix H which was last used in 1994.

The D and E are very similar the only difference being the reverse gear was a little fatter in the E,

When they went from E to F larger layshaft bearings were used.

The G was further improved by all the gear teeth including the pinion getting approx 20% thicker. Also a much wider pump was used to increase the lubrication and cope with the fact that some of the LT 77"s were now being supplied oil cooled, ie V8 NAS 90, 3.9 RR Classic and the 3.5 EFI Discos.

The H (termed the LT 77S) was the same as the G in terms of strength but used a different syncro set up called the "Double Syncro", In reality it didn"t work much better.

I've got a rebuilt D and a used G and couple of LT230 1.222 boxes so I think that I'll try the G and 1.222 first. Down the road I'll likely get an R380.

Keep in mind that Ashcroft's magic supply of short shaft R380s seems to be gone, so you would need to move the engine, AFAIK to put a 300TDI R380 in.

Personally, I don't think there is anything wrong with the LT77 and I suspect a G or H driven by someone that knows how to drive like yourself would last forever.

My box is a 51A.....G also.

I had a G in my 110 and it never gave any trouble... the D in the 90 has not lasted long under similar use.

I was re-reading some stuff and Mr. Ashcroft seems to think the G/H is OK for the 200TDI, but says that any previous suffixes will not last.

So there you go. I guess it is good that my box is a G......as I sure did not look into that before fitting the engine.... :oops: Mine certainly feels/sounds perfectly fine.

I can say that my old G shifted much smoother than the D in the 90 ever has. Only problem with the current G is that is is of unknown history, I hope it is ok.