Hi,
my landy developed weird auto gearbox problem. If you put it in drive it wont move anywhere, but it will shake a little bit, like it is in gear. If you put it in reverse, it works normally. If you maually select first gear, it will move, and if after that you move it to D it will work normally until you stop. Then you have to select first gear to move. Also, when driving normally it will sometimes loose drive on a steep hill.
I have searched for this kind of behavior on this forum, and have found two answers.
1st:
Q
I have a 4sp ZF, when I select "D" the vehicle won't move, when I select "1" the vehicle moves off. I can then select "D" and continue to drive normally. If I stop I have to start in first again. Why?
A
A sprag clutch has "inverted" and will need replacing. No further damage will occur if you continue to drive but you will need to select "1" every time to start moving. A rebuild is required to correct this.
,
2nd:
Another test is to put the selector into 1. If it drives in 1 and reverse then it will be UD2 that is broken, again an easy fix. If not as James says A clutch is favorite and easy repair
There are a couple of unidirectional sprag clutches in them and UD2 breaks, putting it in 1st engages a clutch that bypasses it which is why yours set of in "1", if you get them going and then move to "D" they will change up the other gears ok but if you stop you will need to select "1" to set off again.
Selecting "1" when setting off under heavy load is a good idea as UD2 is a week point in the 4HP. Ashcroft used to do an uprated UD2 which would be worth fitting when rebuilding.
What is UD2 and how easy fix this is? Do I need to take to pull the box to solve this?
Thanks,
Mike
my landy developed weird auto gearbox problem. If you put it in drive it wont move anywhere, but it will shake a little bit, like it is in gear. If you put it in reverse, it works normally. If you maually select first gear, it will move, and if after that you move it to D it will work normally until you stop. Then you have to select first gear to move. Also, when driving normally it will sometimes loose drive on a steep hill.
I have searched for this kind of behavior on this forum, and have found two answers.
1st:
Q
I have a 4sp ZF, when I select "D" the vehicle won't move, when I select "1" the vehicle moves off. I can then select "D" and continue to drive normally. If I stop I have to start in first again. Why?
A
A sprag clutch has "inverted" and will need replacing. No further damage will occur if you continue to drive but you will need to select "1" every time to start moving. A rebuild is required to correct this.
,
2nd:
Another test is to put the selector into 1. If it drives in 1 and reverse then it will be UD2 that is broken, again an easy fix. If not as James says A clutch is favorite and easy repair
There are a couple of unidirectional sprag clutches in them and UD2 breaks, putting it in 1st engages a clutch that bypasses it which is why yours set of in "1", if you get them going and then move to "D" they will change up the other gears ok but if you stop you will need to select "1" to set off again.
Selecting "1" when setting off under heavy load is a good idea as UD2 is a week point in the 4HP. Ashcroft used to do an uprated UD2 which would be worth fitting when rebuilding.
What is UD2 and how easy fix this is? Do I need to take to pull the box to solve this?
Thanks,
Mike
