Series 3 Grind on over-run?

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Rubins4

Well-Known Member
Posts
813
Looking at this month's CLR, there is a report that an out of phase prop shaft can cause an grinding noise on the over-run, a problem I'm facing.

Can anyone shed any light in this? I can understand constant vibration due to poor prop phasing but I can't get my head around a grind on over-run. I thought I'd installed my rebuild prop (rear) correctly following the Green Bible but if any one has an idiot's guide I'm all ears.

Alternatively, anything else to look at?

Cheers all.
 
On overrun the intermediate gear in transfer case is thrust the other way so runs on different part of gear. When people rebuild transfer cases the thrust washers are not always renewed and set up as per manual.
Cannot see how your propshaft can suddenly go out of phase , have you had it dismantled?
 
Yes had both props apart and rebuilt with new UJs all round. I'm afraid I don't know if the grinding was there beforehand. The grinding does go away if you take the roof off, however. :D
 
Looking at this month's CLR, there is a report that an out of phase prop shaft can cause an grinding noise on the over-run, a problem I'm facing.

Can anyone shed any light in this? I can understand constant vibration due to poor prop phasing but I can't get my head around a grind on over-run. I thought I'd installed my rebuild prop (rear) correctly following the Green Bible but if any one has an idiot's guide I'm all ears.

Alternatively, anything else to look at?

Cheers all.
props should be in phase ie both inner yokes in the same plain as in pic below

images

grinding on overrun will be rear diff pinion bearings or t/box output bearings
 
props should be in phase ie both inner yokes in the same plain as in pic below

images

grinding on overrun will be rear diff pinion bearings or t/box output bearings

Now this I can understand.

Best way to check play in either?
 
Newbie here asking, is overrun okay to slow down the vehicle rather than using brakes when coming towards a stop sign and shifting down from 4th to 3rd? I try not to be excessive with this, but it seems to feel okay to let the car slow using the gears this way, rather than throwing it into neutral and using the brakes.
Thanks,
Mike
 
Noise that changes beween drive and over run is usially associated with gears that are helical or spiral as its about the direction of torque pushing things together or apart becuse there is slack. If there is no slack then thre should be no change in the postion and no change in noise. In practice ther is usually some change in sound becuse there is some wear. My ovedrive is quiet under load and overrun and noisey when its between the two. There's a large needbearing in the overdrive and my bet is its hled tight by torque in either dirrection but the rollers vibrate when its off load.
 
It is fine to go down the gears to slow provided it is not in a harsh way that makes the engine rev up hard.It also gets you to or near the right gear to set off again.
 
Newbie here asking, is overrun okay to slow down the vehicle rather than using brakes when coming towards a stop sign and shifting down from 4th to 3rd? I try not to be excessive with this, but it seems to feel okay to let the car slow using the gears this way, rather than throwing it into neutral and using the brakes.
Thanks,
Mike
never throw it to neutral use gears and brakes
 
LR manual has great bit about the gears being the primary way to slow down and the brakes only for stopping. I'll see if i can find it. It think what they are really saying is "the brakes will fade so badly on hills save them unitl you really need them...". I do all my main slowing down on the gears.
Here's the manual:
http://www.retroanaconda.com/landrover/manuals/2a_owners_manual.pdf
 
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I was always taught to sensibly use the gears for slowing in conjunction with the brakes. I always come down through the box when gradually approaching junctions etc.
When I worked for my last company they made us take and advanced drivers course and the instructor insisted that gears are for going and brakes are for slowing. He wasn't suggesting coasting in neutral or anything but I wonder if there has been a change in thinking with modern cars with improved brakes? Or perhaps the newer snowflake generation have limited experience of stick driving!
 
Just had a quick flick through the owners manual, very interesting, especially the tyre pressure table, recommended pressures for the Michelin XY 7.50's on a SWB are incredible low, only 15 psi for normal running.
 
I was always taught to sensibly use the gears for slowing in conjunction with the brakes. I always come down through the box when gradually approaching junctions etc.
When I worked for my last company they made us take and advanced drivers course and the instructor insisted that gears are for going and brakes are for slowing. He wasn't suggesting coasting in neutral or anything but I wonder if there has been a change in thinking with modern cars with improved brakes? Or perhaps the newer snowflake generation have limited experience of stick driving!
the wheels have more control when its in gear
 
Newbie here asking, is overrun okay to slow down the vehicle rather than using brakes when coming towards a stop sign and shifting down from 4th to 3rd? I try not to be excessive with this, but it seems to feel okay to let the car slow using the gears this way, rather than throwing it into neutral and using the brakes.
Thanks,
Mike

Thinking about proper car control- i.e. position, speed, gear, acceleration. The ‘proper’ method is to adjust vehicle speed before selecting a gear to navigate the hazard whatever that may be; so braking or using engine retardation to adjust to the correct speed for the hazard (corner, junction, roundabout etc) then selecting the appropriate gear and accelerating away from said hazard. It’s primarily about setting the car up to be well balanced and having control. Braking whilst changing gear means you have a hand off the steering wheel whilst the car is at its most unbalanced.

In reality driving an old car in my experience, a little bit of engine braking goes a long way. I tend to use engine braking in combination with actual braking - no matter how well serviced my drum brakes are they are essentially ****e... having said that you should be able to apply the system of car control in any vehicle in any situation.
 
Braking whilst changing gear means you have a hand off the steering wheel whilst the car is at its most unbalanced.
you should not be braking while changing gear, you change gear to negate the need for braking as the engine brakes for you.

When I worked for my last company they made us take and advanced drivers course and the instructor insisted that gears are for going and brakes are for slowing.
That was the same when I took my HGV tests recently, however modern truck are fitted with exhaust brakes, which speaking to the drivers at my old work you need to change down a gear to get any benefit from. So it all seems a little contradictory.

In the land rovers I heavily use engine braking, to the point where in the series I managed to get home with no difficulties with virtually no brakes at all after a pipe split. (was only a couple of miles very early morning and was careful with speeds)
 
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