Problem getting into hi-range

[wilkosoft]

Had severe difficulty getting out of lo-range gearbox yesterday.

Eventually it snicked in after a lot of shoving and everything was ok, but I'm worried something's dying slowly.

Is there an easy way to check or do I have to take the floor off?

[Lucy1978]

Are you sure the tranmission wasn't just a bit wound up?

Failing that, I notice from your avatar that you have FWHs how often do you run the truck with them engaged?  4wd/high low selector shafts are all splash lubricated by the turning of the front output shaft, which won't get turned unless the FWH are engaged, so things can get a bit seized up.

There's nothing you can easily visually check as it's all contained within the front output housing of the transfer box, but I can't imagine anythign is slowly dying more likely just needs a bit of use and lube.

here's a bit of a post I wrote for a different forum a while back that may be of interest...


"Stripping my old box down now so I thought I'd open up the transfer box and see how the 4wd system works...

This is the view in through the bottom cover of the transfer box


photo1 – Low Range

Here the transfer box is in low range.
Drive would come in from the main gearbox on the far right of this picture and is transmitted via the intermediate gears in the middle to the output gears on the left.

The following photo shows the transfer box in high range


photo 2 - High Range

Sticking out of the front of the transfer box are 3 shafts

photo 3

The thickest one, at the bottom of the photo, is the front output shaft, which transmits drive to the front axle when 4wd is selected, at its left hand end you can see the dog teeth, and the silver ring of the dog clutch that slides over them to engage 4wd ( see photos 4&5 below.  The one in the middle with nut on the end is the high low selector shaft; this is connected to the red lever.  The top one is the 4wd selector.  The bronze coloured piece attached to it is the 4wd selector fork.


Photo 4 - 2wd


Photo 5 - 4wd

In between the hi/low selector shaft and the 4wd selector shaft there is another short shaft


photo 6
This is the shaft that allows 4wd in high range to be selected. (the photo shows it in low range 4wd)


Photo7

The ‘L’ shaped piece you can see is connected via a lever to the yellow knob.  As you push the yellow knob down it pulls the ‘L’ shaped peg in the direction towards the camera. This disengages it from the short shaft and allows the shaft to move forwards, pushed by the spring on either the hi/lo selector shaft or the 4wd selector shaft (can’t quite work out which), engaging 4wd.


When low range is selected the short shaft is pinned in place by the 'L' shaped peg, so as the hi/low selector is pushed back, by you pulling back on the red lever, the piece that is attached to the short shaft by a pivot and runs between the hi/lo selector and the 4wd selector pivots and pulls the 4wd selector forwards engaging 4wd. This is illustrated in photos 4 and 5.
"

The full thread can be found here...

http://ollr.10.forumer.com/posting.php?mode=editpost&p=36460

[wilkosoft]

What an amazing reply. Thanks.

Yes - I was fretting about the freewheeling hubs and I leave 'em in 4wd all the time how, having decided they're a Bad Thing In General (fuel economy in a '73 land rover? not a priority....)

I may need to top up the oil level in the front transmission....

Thanks for the advice

[wilkosoft]

Actually - I think i've found the problem

Some numpty put the speedo cable through the bracket that holds the 4wd selector lever, so occasionally the cable gets in the way!

Very annoying. Might explain why it sometimes hopped out of 2wd too - guess it wasn't fully engaged.

[Lucy1978]

I like that kind of fix

[Range Rover Blues]

A bit like with air-conn (and I don't mean opening a window) free wheeling hubs need using once a week to move some oil around.  They would be ok as long as you engage them once in a while.