Defender swivel preload value?

[MinniTheMoocha]

My Defender suffered from slight wobbles especially when hitting bumps in the road particularly on the right hand side.

Previously I suspected wheel alignment but had that done about three times and the guys were sick of seeing me.

Checked front bearings and tightened them up a smidge which improved the situation. Installed a new steering damper, radius arm bushes, steering arms, panhard rod and each of them seemed to improve the situation. (These were all done progressively for other reasons not just to improve the wobble! eg. bent steering rod, bushes perished etc)

Well the other week I had to get one wheel swapped over as I had a dent in the rim and would rather the dented one as my spare.

The tyre guys swapped over the tyre to my good rim and away I go. Between 0 - 90km/h no problems so I don't detect it for a few days until I hit the freeway. As I go from 95-100km/h I get the nasty wobbles happening and back it off. I was thinking it was wheel balance had the wheel checked and it was fine so the problem persisted.

Using the search tool on Aulro I located a heap of discussions about this type of problem to check the swivel preload as well as panhard rod bushes, radius arm bushes, steering damper, tie rod ends etc. Now I had done nearly all except the preload.

I read up on Rave and it says the preload should be between 1.5kg and 2.5kg which is what the swivel appeared to have using the spring scales. In the hand however it felt a little loose to me with no real drag/resistance, you could flick it and it would just flop over.

I decided to remove one of the thinnest shims (I had four fitted) and it now has 3.5kg - 4kg preload using the spring scales. In the hand it felt smooth, no notchiness and not overly tight.

Went for a blast down the freeway and no wobbles at all, especially when hitting the sweet spot of 95-100km.

Tomorrow I should be able to give it a good run and hit a couple of bumps that I know upset the front end and report back.

So my questions are is this too much preload? And should the other side be matched with approximately the same preload? Note swivel seals were still in place when tested.

Thanks

[JDNSW]

The preload is not particularly critical. It needs to be enough to ensure there is no free movement and a bit of damping, but it takes quite a bit more to be enough to cause a problem - which would show up as poor self centring. So if it steers OK I would say it is OK. (I don't have any books with me) Note that the preload figure quoted is without seals, so you have to add a bit if the seals are in place.

Some fears have been expressed about shortening bearing life if too tight - but the preload is very small compared to the vehicle weight or shock loads on bumps, so I discount this.

From memory, late Defenders have a roller bearing top and bottom, and this will affect the specified figure.

John

[MinniTheMoocha]

Thanks for the response I think you have nearly responded to all questions re wobbles.

My defender is a 98 and has the dual tapered bearings just as you thought. Does this centre the swivel ball better than old designs?

[JDNSW]

Thanks for the response I think you have nearly responded to all questions re wobbles.

My defender is a 98 and has the dual tapered bearings just as you thought. Does this centre the swivel ball better than old designs?

I don't have enough experience of the double roller bearings to answer that question. I suspect the change was to allow the fitting of ABS units to the swivel rather than to make any improvement to the steering.. It will also mean that there is relatively little damping compared to those with the top bush, making these vehicles more susceptible to wobble.

John

[prith]

My Defender suffered from slight wobbles especially when hitting bumps in the road particularly on the right hand side.

Previously I suspected wheel alignment but had that done about three times and the guys were sick of seeing me.

Checked front bearings and tightened them up a smidge which improved the situation. Installed a new steering damper, radius arm bushes, steering arms, panhard rod and each of them seemed to improve the situation. (These were all done progressively for other reasons not just to improve the wobble! eg. bent steering rod, bushes perished etc)

Well the other week I had to get one wheel swapped over as I had a dent in the rim and would rather the dented one as my spare.

The tyre guys swapped over the tyre to my good rim and away I go. Between 0 - 90km/h no problems so I don't detect it for a few days until I hit the freeway. As I go from 95-100km/h I get the nasty wobbles happening and back it off. I was thinking it was wheel balance had the wheel checked and it was fine so the problem persisted.

Using the search tool on Aulro I located a heap of discussions about this type of problem to check the swivel preload as well as panhard rod bushes, radius arm bushes, steering damper, tie rod ends etc. Now I had done nearly all except the preload.

I read up on Rave and it says the preload should be between 1.5kg and 2.5kg which is what the swivel appeared to have using the spring scales. In the hand however it felt a little loose to me with no real drag/resistance, you could flick it and it would just flop over.

I decided to remove one of the thinnest shims (I had four fitted) and it now has 3.5kg - 4kg preload using the spring scales. In the hand it felt smooth, no notchiness and not overly tight.

Went for a blast down the freeway and no wobbles at all, especially when hitting the sweet spot of 95-100km.

Tomorrow I should be able to give it a good run and hit a couple of bumps that I know upset the front end and report back.

So my questions are is this too much preload? And should the other side be matched with approximately the same preload? Note swivel seals were still in place when tested.

Thanks


I have the same problem, see my post Death Wobble visits me. Will be checking the swivel preload and take it further.

[landroverwa]

Hi MtM,

You may have already resolved this but for what it's worth....

My 08 Defender also developed identical 'wheel shimmy' problems at 95 - 100kmh on the freeway when down in Perth after 12 mths with no problems in the sunny Pilbara.

Had front wheel balance done (they said it was out) and as with you still had the shimmy at precisely 95kmh. Took it to 'specialists' (they said first mob hadn't done it right) and had balanced again - still shimmy. Took it to dealer, they re-balanced in own premises (said previous mob hadn't done it right) and still shimmy. They said probably lop-sided tyre.

Swapped front wheels to back, rear to front and still shimmy at 95kmh.

All other steering gear OK, vehicle steady on road, no wandering.

A friend suggested I ask to have swivel pre-load checked (never heard of it before although 5th Defender!) Pre-load was out and had to be shimmed & problem vanished.

If you have a look at a thread on 25/10/10 "Front diff/hub oil capacity" post #2 by Jock the Rock shows a page from a Defender TD5 on-line workshop manual. Point 47 reads "Check & Adjust Pre-load on Bearings. Resistance after initial inertia is overcome should be 1.16 - 1.46kg. Adjust by removing or adding shims to top swivel pin".

Hope this helps. Good luck!
Keith H.
Karratha
landroverwa

[markyc]

Interesting thread!
I may have the same problem. Could someone please tell me how much dismantling has to be done in order to check this? I looked in the Haynes but it shows the procedure as part of a complete strip down...

Ta!

[JDNSW]

Interesting thread!
I may have the same problem. Could someone please tell me how much dismantling has to be done in order to check this? I looked in the Haynes but it shows the procedure as part of a complete strip down...

Ta!

Checking whether it is a problem is quite simple - jack up the front axle (on stands) and remove wheels (can be done one side at a time, but easier to do both at the same time); disconnect the tie rod (and the draglink on the left side) - this will require a suitable puller or usually judicious use of a hammer on the side of the eye will work; then use a spring balance to measure the force needed to turn the swivel after getting it moving. Since it has the seal in place, add 1-2kg to the book figure, although usually there will be no doubt if it is too loose - it will just flop from side to side with no effort at all.

To adjust the preload is a little more complex. Remove the nuts holding the top swivel pin; remove the bracket holding the brake pipe - to avoid having to disconnect the brake hose, it helps to convert the hole to a slot. Place a jack under the bottom of the swivel housing and then pry up the top swivel pin. Remove shims, retighten, check preload, repeat until you get the right figure. Ideally you need to unbolt the seal, but this will get oil or one-shot everywhere. A shortcut is to remove the entire stack of shims, tighten to the desired load, use feeler gauges to measure the gap, and then a micrometer nor vernier caliper to make up a stack of shims this thickness.

If you find that the preload is significantly less in the straight ahead position, or is not smooth through the full range of movement, then the full strip and replacement of at least some parts is indicated.

John.

[MinniTheMoocha]

Hi MtM,

If you have a look at a thread on 25/10/10 "Front diff/hub oil capacity" post #2 by Jock the Rock shows a page from a Defender TD5 on-line workshop manual. Point 47 reads "Check & Adjust Pre-load on Bearings. Resistance after initial inertia is overcome should be 1.16 - 1.46kg. Adjust by removing or adding shims to top swivel pin".

Hope this helps. Good luck!
Keith H.
Karratha
landroverwa

Hi Keith,

Thanks for your comments, you may have missed in my notes that I did find what the official figure should be but my scales were showing that mine were within the 1.5kg - 2.5kg range. Although I had the swivel seals
in place and as John (JDNSW) says it can add 1-2kg to the reading. To add to the reading I had also left the brake calliper and brake line attached which I am sure affects the force required to move it.

I was worried it might be a little too much preload which is why I posted the question but having read the latest post from John (JDNSW) I am pretty comfortable that it is not excessive.

[MinniTheMoocha]

Just thought I would mention that the "death wobble" is 98% gone .

Normally on my way to work it would happen at the same places. But now it doesn't. I am much more comfortable going above 90km/h and hitting bumps without having the grab the steering wheel in anticipation.

I said 98% because I had some vibration/wobble affect but not at all like the "death wobble" My suspicion is that the left side swivel could also do with some extra pre-load and getting the wheels balanced properly is proving quite difficult.

The reason that the tyre shops struggle balancing the wheels is they simply use a cone to centre the wheel. It does not always work because of wheel offsets and ridges on the defender wheel hub hole. They just keep putting heavier and heavier weights on. The tyre place told me I had a buckled wheel, when they swapped over my spare they said it also was buckled which was impossible as it was a brand new rim! When they showed me the wheel was basically hopping up and down. I got the manager over and he then realised that the cone was not centring the wheel and used an adjustable plate that uses the wheel stud holes to centre it. Was able to halve the weights fitted. Because it was late on a friday before the long weekend and it was already 20 minutes past 5 they were keen to go so I didn't get both front wheels properly balanced nor the spare which was "buckled" I am sure it isn't.

[prith]

Thanks for all the info must get my swivel preload checked.

[dullbird]

Just thought I would mention that the "death wobble" is 98% gone .

Normally on my way to work it would happen at the same place. But now it doesn't. I am much more comfortable going above 90km/h and hitting bumps without having the grab the steering wheel in anticipation.


I said 98% because I had some vibration/wobble affect but not at all like the "death wobble" My suspicion is that the left side swivel could also do with some extra pre-load and getting the wheels balance properly is proving quite difficult.

The reason that the tyre shops struggle balancing the wheels is they simply use a cone to centre the wheel. It does not always work because of wheel offsets and ridges on the defender wheel hub hole. They just keep putting heavier and heavier weights on. The tyre place told me I had a buckled wheel, when they swapped over my spare they said it also was buckled which was impossible as it was a brand new rim! When they showed me the wheel was basically hopping up and down. I got the manager over and he then realised that the cone was not centring the wheel and used an adjustable plate that uses the wheel stud holes to centre it. Was able to halve the weights fitted. Because it was late on a friday before the long weekend and it was already 20 minutes past 5 they were keen to go so I didn't get both front wheels properly balanced nor the spare which was "buckled" I am sure it isn't.

I would also not rule out the 2% being your steering damper...when your swivel preload is out for a long time it can make your damper work overtime and wear it prematurely.

If you have almost got it right I would be inclined to take of the damper and take it for a drive to see whether the 2% has gone or not before making any further adjustment

[justinc]

If you have ABS, as fitted to most Td5 Defenders, then the preload is HALF that of Non ABS models. The lessser figure quoted earlier would've been for ABS model. They have a thrust washer/ bearing/ washer and a pin/ bush assembly in the top instead of 2 taper roller brgs top and bottom.

Excessive swivel preload for ABS models will very quickly ruin the top bearing and thrusts.

JC

[MinniTheMoocha]

If you have ABS, as fitted to most Td5 Defenders, then the preload is HALF that of Non ABS models. The lessser figure quoted earlier would've been for ABS model. They have a thrust washer/ bearing/ washer and a pin/ bush assembly in the top instead of 2 taper roller brgs top and bottom.

Excessive swivel preload for ABS models will very quickly ruin the top bearing and thrusts.

JC

Fortunately mine is non ABS. 1998 300Tdi model, dual 606666 bearings in the swivel. In the next couple of weeks I will take a proper measurement of preload without swivel seals, brake callipers attached etc to know for sure.

That's because the swivels seals are leaking slightly (I run straight 80/90) and will probably use 80/140 so it's a bit thicker and less likely to leak but will replace the seals nonetheless.

Unless somehow this oil is not good for bearings etc.

[MinniTheMoocha]

I would also not rule out the 2% being your steering damper...when your swivel preload is out for a long time it can make your damper work overtime and wear it prematurely.

If you have almost got it right I would be inclined to take of the damper and take it for a drive to see whether the 2% has gone or not before making any further adjustment

The damper is very unlikely for me as I installed it only about 4 or so months ago with a RTC Terrafirma.

Can I just remove one end of the damper, cable tie it to the steering arm or remove it completely?

[JDNSW]

As an addendum to this thread, I will point out what I have in other similar threads.

As with most steering problems, it is unlikely that there is a single problem. It is probably contributed to by a number of minor shortcomings, and fixing any one of these will at least temporarily stop the wobble, until one of the shortcomings gets bad enough to result in wobble even if everything else is perfect.

Wobble is initiated by a number of factors, including out of balance wheels, out of round wheels or tyres, and bumps on the road (the wider the tyre the worse they are likely to affect it). Wheel balance should be the first step.

Its amplitude is limited to the free play in the steering plus free play in the Panhard rod, plus, if it is vigorous enough, any movement in the wheel the driver cannot restrain. Removing all this free play should be done by replacing bushes and tie rod ends. Note that wheel bearing free play shows as steering free play. All of these are more significant for other steering problems than for wobble.

Wobble is maintained by the self centring action, largely the caster action of the caster angle, but partly from king pin inclination. Increased caster angle from raised suspension increases this effect. Larger and heavier tyres help maintain it once started.

The wobble is dampened primarily by the swivel preload (this has the advantage of being before any possible free play), and secondarily by the steering damper. There is probably a small additional effect from the shock absorbers as well.

John

[MinniTheMoocha]

As an addendum to this thread, I will point out what I have in other similar threads.

As with most steering problems, it is unlikely that there is a single problem. It is probably contributed to by a number of minor shortcomings, and fixing any one of these will at least temporarily stop the wobble, until one of the shortcomings gets bad enough to result in wobble even if everything else is perfect.

Wobble is initiated by a number of factors, including out of balance wheels, out of round wheels or tyres, and bumps on the road (the wider the tyre the worse they are likely to affect it). Wheel balance should be the first step.

Its amplitude is limited to the free play in the steering plus free play in the Panhard rod, plus, if it is vigorous enough, any movement in the wheel the driver cannot restrain. Removing all this free play should be done by replacing bushes and tie rod ends. Note that wheel bearing free play shows as steering free play. All of these are more significant for other steering problems than for wobble.

Wobble is maintained by the self centring action, largely the caster action of the caster angle, but partly from king pin inclination. Increased caster angle from raised suspension increases this effect. Larger and heavier tyres help maintain it once started.

The wobble is dampened primarily by the swivel preload (this has the advantage of being before any possible free play), and secondarily by the steering damper. There is probably a small additional effect from the shock absorbers as well.

John

This sounds just like my situation. One of my other posts was about bearing play. I have been trying to get to the bottom of this problem and working through each of the possible issues. (slowly I might add)

It was lifted with new springs and shocks (shocks were shot! and I was sagging badly) which resulted in a much better ride and less of a problem.

I put in castor correcting bushes which did help with wandering and steering feel. But got a bit of vibration from front drive shaft (yet to be replaced with DC or wide angle yoke) due to diff angle.

Then got an alignment which improved tracking.

Tyre tubes needed to be replaced (two flats in about three weeks) and the problem was back with vengeance. Got wheel balance which improved it quite a bit.

Swapped over to my muddies and for quite some time it improved. Had to swap rims on the muddies and the problem resurfaced badly. (Wheel balance definitely a contributing factor)

Replaced steering arms (bent them) but this included all new tie rod ends.

Replaced damper with RTC to improve steering.

Replaced Panhard rod with adjustable type to improve alignment as originally only used standard one (this included new poly bushes, I normally use rubber but think this is one area where the poly's would be fine)

Finally adjusted preload which I should have looked at earlier because I am pretty sure the right side was too loose as it swung fairly freely.

I am still sure wheel balance is contributing a little and will get a proper wheel balance all round because as mentioned earlier the tyre place had a hard time getting it centred properly.

But now having done the preload on the right side my confidence is back!

Thanks to all contributors.

[prith]

The damper is very unlikely for me as I installed it only about 4 or so months ago with a RTC Terrafirma.

Can I just remove one end of the damper, cable tie it to the steering arm or remove it completely?

HoW is the RTC Terrafirma damper. Am changing mine to that hopefully! Need to get rid of the death wobble.

[dullbird]

HoW is the RTC Terrafirma damper. Am changing mine to that hopefully! Need to get rid of the death wobble.


You would be better off fixing the wobble and then fitting the damper..not fitting the damper to mask a problem

[MinniTheMoocha]

HoW is the RTC Terrafirma damper. Am changing mine to that hopefully! Need to get rid of the death wobble.

I agree with Dullbird. Do preload first, hopefully this is your problem too then look at replacing your damper if it is worn out or you would like the benefit of having the spring assistance.

[MinniTheMoocha]

Well I checked the preload on the left hand side and found it to be < .5kg with the swivel seal still in after initial pull on the spring scales.

So that is pretty low.

Set it to be about 2kg removing one shim.

Still a wheel alignment left to do is get rid of a slight vibration but I have been happily hitting bumps at highway speeds and no "death wobble" to speak of.

[BilboBoggles]

I've had the death wobble for the last 100,000k's on my TD5. Only happened when turning right and hit a bump. Steadily got worse and worse. Recently did a suspension overhaul, with new springs and dampers. It's like new again - with no wobble at all. (I'd previously tried all of the above suggestions - but had not thought of the shockers!)

[MinniTheMoocha]

I've had the death wobble for the last 100,000k's on my TD5. Only happened when turning right and hit a bump. Steadily got worse and worse. Recently did a suspension overhaul, with new springs and dampers. It's like new again - with no wobble at all. (I'd previously tried all of the above suggestions - but had not thought of the shockers!)

Well at least you checked the preloads.

I worked a little in reverse and having done all the other things resorted to finally checking them.

Would still have replaced the other kit but it would have made it easier to drive than worrying about the next bump I was going to hit.

[troppojon]

is there a trick to undoing the bolt that holds the brake hose bracket?

[abaddonxi]

is there a trick to undoing the bolt that holds the brake hose bracket?

Put a jack under the bottom of the swivel.

[MinniTheMoocha]

is there a trick to undoing the bolt that holds the brake hose bracket?

You have to keep the socket vertical to the bolt head and use the thinnest socket you have available.

If I had a die grinder I would trim the brake line bracket so you can fit a normal socket on it!