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Post 36
March 2016

Transfer Box Assembly

land rover series 3 transfer box inside

I didn’t remove the output shaft. The bearing is pressed into the housing and must be driven out. I could’t get it to budge with moderate hammer blows and don’t have a press. In any case everything seemed OK so there was no point wrecking something for the sake of complete dismantling.

land rover series 3 transfer box intermediate shaft

New roller bearings for the intermediate gear. These were about all I changed inside the transfer box. I had no reason to go hunting for problems, everything worked fine before I pulled it apart, so all I replaced were bearings and gaskets, and a couple of shims. Gears all looked fine.

land rover series 3 transfer box intermediate shaft fixing

End of the intermediate shaft. The shaft is a very gentle tap fit. The chamfer provides clearance for the speedometer cable, so this needs to be around the right way.

land rover series 3 transfer box with speedometer housing

Speedometer housing fitted to transfer box. There are about 10-15 shims between the speedometer housing and transfer box which set the preload for the output shaft bearing.I had pre checked all of this in case I needed to order more shims (post 29). I smeared the shims very lightly with grease before fitting to prevent rusting (as some of the old ones had). I came back and loosened and re tightened the nuts after it had been sitting compressed for a while, just to make sure the grease had been fully squeezed out and wasn’t effecting the preload.

land rover series 3 front output housing

Front output shaft assembly. The lever thing is where the Yellow Knob goes. There is a complicated arrangement of three shafts that all interact to select low range, 4wd, 2wd.

land rover series 3 front output housing

Here are the three shafts. The large shaft with the O ring is the Red Knob. The other two are connected to nothing, but react to the movement of the Red Knob and whether or not the Yellow Knob is preventing the centre shaft from moving.

land rover series 3 front output housing

Fitting the cover for the shafts ends. This was full of rust when I pulled it apart. There is no gasket between the cover and the output housing so water finds its way in and sits inside rotting away the cover and the ends of the shafts. Before refitting, I half filled the cover with grease, and used gasket sealer on the mating face.

land rover series 3 front output housing

Output shaft housing about to join with the transfer box. This is requires lining up one of the shafts with a selector fork in the transfer box while sliding the whole lump together. A bit fiddly but clomps into place when right.

land rover series 3 low range selector fork fixing

This is the fixing of the low range selector fork to the Red Knob shaft. Some muppet in the past had replaced this bolt with a BSF acme threaded bolt. BSF ACME! Probably the rarest bolt thread on the planet. The bolt was obviously munched when it came out, but thankfully the thread inside the selector fork was OK, and a standard new BSF bolt threaded in no problem. Lucky.

land rover series 3 low range selector springs

The little springs and balls that make shifting the Red Knob so stiff. Why did land rover use two completely different ball and spring arrangements within of few inches of each other doing exactly the same job?

land rover series 3 transfer box assembly