Juddering When In 4WD

[Ian B]

When I engage 4WD in my Land Rover (1976, Series 3, 109, petrol) it is fine in a straight line but when cornering or turning at T-Junctions it starts to judder and the steering-wheel starts to jerk around. It also slows the vehicle down as though something is fouling. On full-steering-lock it can barely move which makes parking very difficult!
In 2WD there is no problem, even on full lock. Thanks in advance for any suggestions.

[steve-p]

Prior to 90/110/Defender, there was no centre diff. That means when you select 4wd, you get transmission windup when turning, if there is good grip at all of the tyres. This makes the steering reluctant to turn the car and feel heavy, because the front and back axles want to turn at the same speed, but when turning, the back axle travels a shorter distance. The juddering is the tyres being forced to slip. However, it can break the transmission too. You should only be using 4wd if the wheels are able to slip to a degree. Unfortunately where roads are part icy and part clear tarmac, that's difficult. Normally, with the Series part time 4wd system you would never use 4wd on a road. Post-1983 Land Rover transmissions are full time four wheel drive with a centre diff which is lockable for really difficult conditions, but when unlocked, the transmission behaves normally on any surface.

[fish]

Except in the Stage 1 V8, I've got a centre diff and diff lock....Range Rover transmission.

[Ian B]

steve-p said:

Prior to 90/110/Defender, there was no centre diff. That means when you select 4wd, you get transmission windup when turning, if there is good grip at all of the tyres. This makes the steering reluctant to turn the car and feel heavy, because the front and back axles want to turn at the same speed, but when turning, the back axle travels a shorter distance. The juddering is the tyres being forced to slip. However, it can break the transmission too. You should only be using 4wd if the wheels are able to slip to a degree. Unfortunately where roads are part icy and part clear tarmac, that's difficult. Normally, with the Series part time 4wd system you would never use 4wd on a road. Post-1983 Land Rover transmissions are full time four wheel drive with a centre diff which is lockable for really difficult conditions, but when unlocked, the transmission behaves normally on any surface.

Thanks for the explanation Steve, I never thought of it like that. I'm glad there's nothing expensive wrong!

[fish]

The early series were only designed to use the 4wd OFF road in slippy conditions, or when very slippy on road ie solid ice/snow.

[Ian B]

Mine has freewheeling hubs, is there any benefit to having them engaged but staying in 2WD? ...other than not having to get out of the vehicle to change to 4WD when needed.

[fish]

Freewheeling hubs disconect the front diff and axle to reduce fuel bills and improve economy as when you drive along you are not having to turn the axle and diff over. It does mean you have to lock them though to get power to the wheels.

If you are doing general driving 99% time your hubs should be set to 2wd and you should use 2wd. If you know it is going to snow or you are going off road set them to 4wd so you can employ 4wd just by using the selector.

[seaton]

Ian B said:

Mine has freewheeling hubs, is there any benefit to having them engaged but staying in 2WD? ...other than not having to get out of the vehicle to change to 4WD when needed.

You realy should engage them about once a week for a few miles, as the rotation of the half shafts flicks oil up to lubricate the top swivel pin's.

[Mrs Fish]

James here:

good point that one. we never used to bother, however it did go off road every couple of weeks

[Mrs Fish]

Yep good point, our old one used to go off road every two weeks though so it was never a prob

[Mrs Fish]

Yep good point, our old one used to go off road every two weeks though so it was never a prob

[Mrs Fish]

Yep good point, our old one used to go off road every two weeks though so it was never a prob