Thread: high ratio transfer gears

Originally Posted by isuzurover

Have you actually tried fitting 9.00's to a civvie series???

Hitting the springs??? The WMS-WMS measurement of a one-ton is the same as a standard series.

Hitting the guards??? Possibly an issue on the rear, but nothing a slight trim wouldn't fix.

I think you need to try it before you mislead people Diana. IRC Slunnie tried 37s on one of his series landies.

Originally Posted by hillbilliywheelchair

cut the gards out extend the bump stops and they fit fine

Ben

I don't have to - I know what happens on a standard vehicle with standard tyres and I know the differences with 9.00 tyres and military chassis so i can work it out from first principles. Further to that I don't have or know anyone locally with a standard civvy series vehicle and the last one of that type I owned myself was in 1981.

The 1 ton is sitting on what is essentially the same as an au military chassis, which has something like a 2" lift.

If you have standard suspension on a standard civvy chassis and push the bump stops down by 1 1/2" - 2" to stop the tyres rubbing on the under body surfaces, you have reduced the suspension travel by exactly the same amount as your blocks. If there is only about 6" upward movement on the front originally and you've reduced it to 4" you have reduced upward movement 33% and that happens on both sides you have reduced your articulation.. I still believe that a 33% reduction in suspension travel is a lot. Even if it is only the upward movement 16.5% reduction is still a lot.

Moving from 6.50 or 7.00 to 7.50 tyres you have to wind the steering stops out to prevent them rubbing on the inner guards and springs already. With 9.00 tyres it will be worse! 1 Ton Land Rovers have appalling turning circles because of this factor. (Have you ever driven or even been near a 1 Ton series Land Rover - I have.)

The minimum rim width for 9.00 tyres (XZL) is specified as 6.5" by Michelin. forward control 6.5" rims are as rare a rocking horse poo. The current Defender 130 and Disco I rims have a positive offset when compared to F/C rims. This will make the situation worse.

If he really wants to try the situation tell him to bring the standard suspension LR over to our farm and he can try on a set of 9.00 16 tyres. Although it won't be a fair test because most of mine are on SIIB rims the most negative offset of all the LR rims.

Diana

Originally Posted by praxis

Hi all, could I ask a basic question on the original topic, please? To fit the Ashcroft high range gears to 41mm shaft transfer case does the case have to be remachined? OR - do the Ashcroft gears slide straight in?

The old intermediate shaft hole needs to be welded up and a new hole machined in a different spot. As it is a 3-gear in-line case (high range), If you just changed the tooth counts, the overall drive ratio would remain the same.