Universal Joint failure

is200 Newbie · June 22, 2017

Has anyone experienced a Universal joint failure (driveshaft) I haven't pinpointed which side yet (passenger or driverside rear) ... are there any on the fronts as well?

Looking to diagnose a vibration and may have possibly found the answer - would a failing joint cause vibration and to what extent?

Shahpor · June 23, 2017

You mean the CV joint?

It is rare for them to fail unless the boot surrounding them splits and all the grease leaks out.

Also, no CV joints on the front since there aren't any driveshafts, only hubs.

Can you describe the vibration?

is200 Newbie · June 23, 2017

1. There's no indication as to where the vibration is coming from

2. It happens when decelerating (foot off gas) when going downhill or even down a gradual incline when your foots off the gas with car still running

3. Doesn't matter if its in Auto or manual (car is an autobox), the vibration happens in each setting

4. Cruise control on and when the car is (as in 2. above) decelerating it will happen then.

5. Acceleration above 60 it will vibrate but not noticeable in the lower gears.

Best way I can describe it is that its a shudder (felt throughout the car (front and back passengers can feel it.) and more pronounced when at speed. Its slowly getting worse but I have done almost 2k miles in it this week which doesn't help so I have managed to have a good listen and feel to see whats going on. I have the following thoughts...

Carbon build-up - car is on 103k miles now, can do with a clean I reckon and was thinking along the lines of a terraclean to see if that helps
Spark plugs - is my next job when I get a chance. Not sure if the plugs can get to a state where they can cause a vibration - possibly not burning fuel correctly or causing a slight missfire? There is a slight roughness at idle when starting from cold in the morning and the exhaust tips are sooty
There are no fault codes being thrown up - none stored.
Torque convertor - have read about issues in the states where this is a symptom of it starting to go.
Universal joint - (U-Joint) is how an issue is described on a forum for Chevys http://forums.trailvoy.com/showthread.php?s=b79b3e6af7daae129a278b2173ea03e8&t=64409&page=2
Its comes across as a rhythmic rotational vibration so I am certain its mechanical and happens when at speed and decelerating.
Tyres / wheels / brakes / exhaust / fluids are all ok.

I cant narrow it down any further than that - I can check the U-Joint for excessive play quite easily (I will check the drive shaft coupling which is a better word for the U-Joint) These are not too expensive to replace. The spark plugs and carbon clean I can get done which leaves me with the torque converter - if that's the issue then the car is scrap.

I can throw £1000 at it for all of these bits (apart for the convertor) to see if it can be resolved but after that its not worth it to carry on and will be a sad day to see it go. I am sure the convertor is around £2500 to replace (fitted) if that's the issue.

is200 Newbie · June 23, 2017

One more point - MPG is not down either

Shahpor · June 23, 2017

Ok, for the sake of clarity, I am referring to the parts in red:

Hmm, strange one. Although I would have through that some of the items you described would make it shudder when accelerating, not decelerating.

You say it does it over 60mph, so is that all the time (i.e. regardless of acceleration or not)?

Have you checked the wheel bearing?

When decelerating, does it go away as the speed comes down or does it do it until you have stopped?

is200 Newbie · June 24, 2017

10 hours ago, Shahpor said:

Hmm, strange one. Although I would have through that some of the items you described would make it shudder when accelerating, not decelerating.

You say it does it over 60mph, so is that all the time (i.e. regardless of acceleration or not)?

Have you checked the wheel bearing?

When decelerating, does it go away as the speed comes down or does it do it until you have stopped?

It is a strange one

It will shudder over 60mph when accelerating and gets worse with speed over that point. It will also do this when decelerating from this point up to 60mph then stop, by decelerating I mean taking foot off gas so letting the car slow itself down. That was why I was thinking torque convertor as the engine is using the convertor to slow as its not under any pressure from the car in forward motion (if that makes sense?)

I checked the bearings when I first experienced this and no play at all. Its not a bearing noise to be honest so I am confident its not those.

When decelerating (as above, foot off gas) it will disappear at around 60 to 70 mph. It can be felt very very slightly but I guess I know its there so I am looking for it.

Thanks for the diagram - the part I am suspecting is below - not sure on how this puts out movement to the wheels though - I guess all the joints and stuff are within the rubber boots so its not hard to see them unless the boots have split. A recent MOT would have picked this up but it didn't and the shudder has been going on prior to the MOT.

I am thinking that, when accelerating, the shaft is constantly in "drive" so its pushing on other parts and so it wont create a shudder vibration as its in continual pressure on these parts but when decelerating it wont be under as much pressure pushing on other parts so effectively it will be "loose" a bit and can create the shudder? but this does not explain why it happens noticeably worse over 70mph

Best guessing this --- I am not a mechanic and i know its hard to diagnose things like this by not experiencing them - it kind of makes sense really as to where the shudder is coming from but if anyone can explain how these drive shafts work then that would help - I believe there is one on passenger and one on driver side. Not sure of the front sides. It feels like it is coming from the front but I know that can be deceptive. No shudder from pedals or steering wheel also.

I guess if it was any issue with engine or tranny mounts then that would be obvious at any speed but its on my list to check. I have no distance to do now in it, just local driving and have time in a couple of weeks to look at it so will do a bit more research to see what it could be - indications from other sites are suggesting this shaft so will look at that first but a bit more info would be helpful.

Shahpor · June 24, 2017

Ok, so the propshaft takes the drive from the engine and transfers it to the rear differential. The differential splits the motion into two and send it to each rear wheel. The drive shafts transmit this drive from the differential to the wheels. The reason the drive shafts have two CV joints is because the wheels have to move up and down while the differential stays still. This diagram shows what's inside one:

So, as you can see in the following picture, inside the rubber boot is a set of ball bearings in a cage:

What usually happens is that, when the boot splits and the grease is lost, the ball bearings will wear and develop play against the cage. This will eventually lead to failure if the joint isn't replaced. On the whole though, they are very strong joints and rarely fail.

Removing the shaft isn't the most difficult of jobs, and can be done with regular tools. Once out, it can be checked for wear.

So, because the IS is rear wheel drive, there are no drive shafts on the front axle. Only front and four wheel drive cars have drive shafts on the front.

I get what you are saying regarding the shuddering, although I have probably missed what you said, but what happens to the car below 60mph?

I had a bad shudder on mine that turned out to be engine mounts, but mine only happened during initial acceleration.

Worst comes to worst, you can always book it into a dealer to see if they can figure it out? It would cost you a bit, but I would expect a definitive answer for my money. It would probably be better than just randomly changing parts.

jackcramerr · June 24, 2017

Any relationship to RPM?

Check exhaust mounts and exhaust. They should all free hang from rubber mounts and you should be able to shake it. Should not be stiff. I think you know more on this subject.

Wisty · June 25, 2017

Are the tyres in good condition? A previous car had an intermittent judder at certain speeds and under certain conditions - this vanished when the tyres were changed and the wheels properly balanced. Just a thought.

is200 Newbie · June 25, 2017

18 hours ago, jackcramerr said:

Any relationship to RPM?

Check exhaust mounts and exhaust. They should all free hang from rubber mounts and you should be able to shake it. Should not be stiff. I think you know more on this subject.

Its only applicable within a small RPM band due to the speed it happens at. I cant associate that to anything. Exhaust is all good. It actually started before I done my new exhaust so cant associate it to that unfortunately.

1 hour ago, Wisty said:

Are the tyres in good condition? A previous car had an intermittent judder at certain speeds and under certain conditions - this vanished when the tyres were changed and the wheels properly balanced. Just a thought.

Tyres are good all round - its not that sort of shudder that I can relate to any tyre condition

I am coming to the conclusion that its an issue with the drive shafts (don't know which side yet but I will replace both sides I think as they are both as old as each other) It needs to go on a ramp to see if there are any issues associated to the shaft first but it does make sense thinking its one of them (or both)

There is however a rubber flex disc (guibo) that I "think" could be worn and associated to the shuddering as the associated noise with the shudder is muffled (not metal on metal) indicating it could be rubber banging around, this looks to be connected to the main drive shaft - i think its worth a go to get it checked out ?

HOWEVER - CAN I FIND ONE OF THESE FLEX DISCS/GUIBO - CAN I HELL.. ABSOLUTELY NOWHERE !!!

DOES ANYONE KNOW A PART NUMBER? (EVEN SOURCING FROM THE STATES)

Picture of another cars is below...

is200 Newbie · June 26, 2017

Car is booked in next week to diagnose this , booked into a local indie I trust.

I am hoping its the drive shafts and not the main prop .... cost for the rubber disc is ..... wait for it ........ wait for it ........ £1048 !! ... + VAT (so £1257) !!! (OEM part supplied from Lexus)

But on the upside that does include the shaft as well !! - pretty useless when all that could be required is what is basically a rubber washer !! I could use the prop shaft as a washing pole I suppose tho!

Shahpor · June 26, 2017

That is ridiculous! I bought a couple of guibo's over the years for various BMW's and they were cheap and easy to install. The fact that Lexus won't supply just that part is scandalous.

If it turns out the be the guibo, I would just find someone breaking a 250 and get a second hand one from them. Not ideal, but it is not the most difficult thing to change if you need to do it more than once.

I am obviously curious to hear the results, so keep us posted please.

Monocle · June 27, 2017

My experience of a CV joint failure is that it is noisy rather than it creates a vibration. So, you would probably hear a CV joint failure before you would feel it. Unless of course you see the boot leaking first!

On 6/25/2017 at 0:46 AM, jackcramerr said:

Any relationship to RPM?

This is important. Your description would indicate that it is related to speed rather than rpm so the vibration can only be from the gear box and back.

A vibration is generally caused by an imbalance (natural frequency is another but this wouldn't appear all of a sudden). There is unlikely to be an imbalance in the prop shaft so, unless it is loose, I would discount this. And if it is loose you should notice the vibration at low speeds too - there would be a very gradual build up of vibration intensity with speed - not just over 60mph.

From what you describe above, it seems like a tyre/wheel imbalance is most likely. Could one of the weights have come off? As the wheel is the only part of the drive system that is "cantilevered" it will accentuate vibration. Under drive conditions, vibration is generally less than when in free rotation. I speak from experience of balancing industrial fans so I hope the same logic applies here!

is200 Newbie · June 27, 2017

7 hours ago, Monocle said:

My experience of a CV joint failure is that it is noisy rather than it creates a vibration. So, you would probably hear a CV joint failure before you would feel it. Unless of course you see the boot leaking first!

This is important. Your description would indicate that it is related to speed rather than rpm so the vibration can only be from the gear box and back.

A vibration is generally caused by an imbalance (natural frequency is another but this wouldn't appear all of a sudden). There is unlikely to be an imbalance in the prop shaft so, unless it is loose, I would discount this. And if it is loose you should notice the vibration at low speeds too - there would be a very gradual build up of vibration intensity with speed - not just over 60mph.

From what you describe above, it seems like a tyre/wheel imbalance is most likely. Could one of the weights have come off? As the wheel is the only part of the drive system that is "cantilevered" it will accentuate vibration. Under drive conditions, vibration is generally less than when in free rotation. I speak from experience of balancing industrial fans so I hope the same logic applies here!

Thanks Peter

A lot of people have suggested tyres - its not that sort of shudder and noise I would associate to tyres but for the ease of checking it I will get this done in the next few days as theres an ATS near where I work.

Regarding the associated noise - its a dull low down noise which I would expect from rubber hitting metal - the shudder it there in low speeds but you have to really know its there and listen/feel for it as its not that obvious.

The garage is going to check all the moving joints that they think it could be coming from - easier for them as they can get it on a ramp to do this. One thing I did notice a while ago and I thought about it today, there was a feeling the back end was going out when cornering more than it should (when turning right), maybe associated to a worn drive shaft? or some other associated gearing?. How noisy would it be if it developed the noise first. I have the music on not loud but loud enough not to notice outside noise.

Coming home today I put the car in N when I was stopped at lights and revved it a bit and it was very smooth - at the weekend I drove it on the motorway and placed it in N but the shudder still happened. Seems to indicate its while its being driven / moving under load that the shudder is happening - rules out a few things I guess, I am just hoping its not the torque converter else I am afraid it would be a scrapper as I would not really trust an indie to do this work in replacing gearbox parts to do the work on one of these cars and the dealer cost (I have not even considered)

is200 Newbie · June 27, 2017

19 hours ago, Shahpor said:

That is ridiculous! I bought a couple of guibo's over the years for various BMW's and they were cheap and easy to install. The fact that Lexus won't supply just that part is scandalous.

If it turns out the be the guibo, I would just find someone breaking a 250 and get a second hand one from them. Not ideal, but it is not the most difficult thing to change if you need to do it more than once.

I am obviously curious to hear the results, so keep us posted please.

I have seen these separate guibo's available for BMW and other makes - Its not been diagnosed as that being the problem (yet), the issue I have fits with a lot of other makes of cars with their owners experiencing this. Guess I have my negative head on. It may be worth keeping in mind to try the closest fit or like you said, trying a scrap dealer. Will keep you posted

Monocle · June 27, 2017

Well it seems like a tough one to call all right.

Hopefully you can get it diagnosed easily and with not much cost.

Btw, this is a long shot and highly unlikely, but I had a front wheel bearing fail on an old car years ago and I replaced the whole hub. But I used the old hub nut instead of a new one (spring nut I think it is called) and it came loose. There was a significant shudder as a result that did increase with speed and was worse when not under load. Anyway, I doubt that is your problem but maybe worth sharing!

Best of luck with it - never want to see an IS leave our roads

jumbojake · June 28, 2017

vibration at specifc speed would suggest a tyre as opposed to mechanical problem, but nt sure if it fits all of the symptoms .

no idea if relevant, but when as your diff oil last changed?... it is a regular service item, and I can imagine it being missed ... cheap, quickd and worth a try, certainly not do any harm

is200 Newbie · June 28, 2017

35 minutes ago, jumbojake said:

vibration at specifc speed would suggest a tyre as opposed to mechanical problem, but nt sure if it fits all of the symptoms .

no idea if relevant, but when as your diff oil last changed?... it is a regular service item, and I can imagine it being missed ... cheap, quickd and worth a try, certainly not do any harm

Cheers - I am having the tyres checked tomorrow

Since I have owned the car the diff oil has not been changed (not sure if it was done before either - (I have owned it from 60k miles) - I was not aware that this was part of the schedule although it was my intention to do it a while back as I looked into getting the drain plug washers but I am sure there was a reason I never done it. I think I brought it up on the forum but there was a reason why not to do it?

It can be checker or rather changed as part of the process of finding the issue - can ask the garage next week to do this as don't expect it to be a big job.

is200 Newbie · July 4, 2017

I have bottomed this problem out (hopefully)

Thanks for the pointers to the wheels being imbalanced – it was a part of the issue but not one that noticeably stood out, I took the plunge with one of the first jobs I had on my list to do to see if there were any issues. I had the rear wheels removed, one by one, and had the tyres removed to check the inner alloy for corrosion.

Found the inner rim where the tyre sits and seals to the rim was corroded badly on both but worse on one. Had the front tyres removed and the same, one was bad and one not too bad.

Tyre pressures – I regularly check the pressures and top up as required. I generally use the car around town – small journeys with the occasional long one – when I noticed the shudder more it was over two months where I put quite a bit of motorway miles on the car and obviously at higher speeds than that done around town. I didn’t check the pressures during this time as there was no air machine in the petrol garages I used to fill up in..

When I checked the pressures when used around town they were all within a couple of psi tolerance – I set the fronts to 35 and the rears to 38 so I was happy with that as it allows for the cold weather conditions and the wheels / tyres not coming up to temp. When I measured the pressures after the long journeys they were all over the place – measuring at rears, 20psi / 30psi fronts at 30psi and 32psi. So I am thinking due to the wide varying difference between around town driving and the motorway driving then heat will have been the indication in possibly relaxing the seal of the tyre on the corroded wheels as it lost pressure from when it was being driven over a long distance (1 x 800 mile round trip and 1 x 700 mile round trip)

The inner rim has been cleaned up as best as can be for now but am expecting it not to last. I will leave it for a while just to see if that was actually the issue – it seems to be behaving now with no shudder on a short run I done. Am not ruling out the shafts as the issue fits with the symptoms of a failing one but if the wheel rim clean has cured it then I think I will be changing the wheels – may keep these for winter tyres to go on.

If I am looking for new wheels I will be putting on 18”s – what wheel sizes should I be looking for and ideally the tyre size?

bobmc · July 4, 2017

Well that's encouraging if it is just the tires and wheels rather than some difficult to diagnose suspension issue.

If sticking to standard tyre sizes, then the wheels should 8.5j rear / 8j front - offset 45mm CB 60.1

These look really nice on the IS if you can find a set

http://www.ebay.com/itm/Lexus-18-G-Spider-Staggered-WHEELS-SET-w-Center-Caps-OEM-Genuine-/131010690964

is200 Newbie · July 4, 2017

9 minutes ago, bobmc said:

Well that's encouraging if it is just the tires and wheels rather than some difficult to diagnose suspension issue.

If sticking to standard tyre sizes, then the wheels should 8.5j rear / 8j front - offset 45mm CB 60.1

These look really nice on the IS if you can find a set

http://www.ebay.com/itm/Lexus-18-G-Spider-Staggered-WHEELS-SET-w-Center-Caps-OEM-Genuine-/131010690964

I am hoping it is the wheels - quite an easy repair and wont cost £1000's

I have seen these style before, come up from time to time on eBay. They are a nice style.