Jump to content

Unstable at High Speeds


maxrep2003

Recommended Posts

2002 Land Rover Discovery II

Has anyone experienced extremely poor handling when traveling at high speeds (55-80mph). I've experienced a lot of pull when traveling at these speeds. So much so, that my truck will pull to the left and/or right, severely and without warning. I've also experienced general instability where it feels like I'm losing control of the truck at these high speeds. This problem happens when traveling straight or generally straight. HELP!

Link to comment
Share on other sites

General order of things to look at is:

1) all the steering related ball joints

2) the swivel bearing preloads

3) the suspension bushes.

My money would be on sloppy swivels when you hit undulations in the road ... really bad ones can induce serious bottom clenching moments!!

AndyG

Link to comment
Share on other sites

4) Shock absorbers.

One on my front shocks had partially collapsed and was floating for the first 1/2" of travel or so, made it noticably unstable esp in cross-winds in conjuction with the worn tie-rod ends I had. Both fixed a few days apart, now back to normal and much more relaxing to drive.

Anything that allows the front-end toe angle to change unexpectedly would be my first port of call (tie-rod ends (ball-joints), bearings, swivels, etc as previously mentioned by others).

I had Goodyear ATRs (245/70R16) on mine and they were bl00dy awful. Tried every tyre pressure and front/rear combo known to mankind and they were still awful in differing degrees. Had the local Goodyear engineer take a look and he reckoned they were OK... Vehicle would tramline, follow anything on the road, responded slowly to steering input yet felt nervous(!?), etc. Was constantly sawing at the wheel to keep it in a straight line. Never again. The BFG AT 225/75R16s I had before that were really nice, as are the Kumho KL71s (31x10.5R15) I now run.

Link to comment
Share on other sites

4) Shock absorbers.

One on my front shocks had partially collapsed and was floating for the first 1/2" of travel or so, made it noticably unstable esp in cross-winds in conjuction with the worn tie-rod ends I had. Both fixed a few days apart, now back to normal and much more relaxing to drive.

Anything that allows the front-end toe angle to change unexpectedly would be my first port of call (tie-rod ends (ball-joints), bearings, swivels, etc as previously mentioned by others).

I had Goodyear ATRs (245/70R16) on mine and they were bl00dy awful. Tried every tyre pressure and front/rear combo known to mankind and they were still awful in differing degrees. Had the local Goodyear engineer take a look and he reckoned they were OK... Vehicle would tramline, follow anything on the road, responded slowly to steering input yet felt nervous(!?), etc. Was constantly sawing at the wheel to keep it in a straight line. Never again. The BFG AT 225/75R16s I had before that were really nice, as are the Kumho KL71s (31x10.5R15) I now run.

Interesting... My RRC had 'the wanderlust' and I found that it had knackered shocks (about 2" of damperless travel) and swivel hub preload too high (This is as it came from a 'reputable' Land Rover specialist dealer!). Once I sorted these two the wandering improved dramatically but it still wasn't good. Never thought of the tyres since they were Kumho AT somethings - I just assumed that they would be ok. Mine was better when towing a trailer :huh: What's that about? :lol:

Biggest effect of anything I did in this area was change the dampers - even though I put cheap ones on they TRANSFORMED the handling all round.

TwoSheds

Link to comment
Share on other sites

Interesting... My RRC had 'the wanderlust' and I found that it had knackered shocks (about 2" of damperless travel) and swivel hub preload too high (This is as it came from a 'reputable' Land Rover specialist dealer!). Once I sorted these two the wandering improved dramatically but it still wasn't good. Never thought of the tyres since they were Kumho AT somethings - I just assumed that they would be ok. Mine was better when towing a trailer :huh: What's that about? :lol:

Biggest effect of anything I did in this area was change the dampers - even though I put cheap ones on they TRANSFORMED the handling all round.

TwoSheds

Tyres are massively important. Hey, they're the only things attaching you to the road/track/rock/fallen log. Different tyres will behave differently on different vehicles on different rims or different surfaces. Work out the cost per km/day/whatever and they're still cheap insurance.

After tyres, I'd agree that dampers are seriously underrated and overlooked. Most dampers are past their prime in only about 2-3 years and start to degrade towards dangerous not long after that, depending on usage/quality/etc. IMHO it's better to replace them regularly and get good value for money units, rather than dumping a month's salary on a set and then leaving them in there for the next decade...

Maybe the trailer improvement was due to the increase in overall mass, effectively damping out some of the sway? Dunno.

Link to comment
Share on other sites

I am assuming that the Disco is equipt with ACE (Active Cornering Enhancement) . I have seen a similar instance of the ACE doing funny things and unstabling the vehicle at high speeds. If so get it checked out by a dealer/some one who can diagnose ACE.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...

Important Information

We use cookies to ensure you get the best experience. By using our website you agree to our Cookie Policy