Vibration At 70Km/h And Higher

[konect]

Hi all,

Been trying to fix this for over a month now so thought I'd create a thread on here to see if anyone has had something similar. I've tried to summarise as best as I could.

Car info:

• Cefiro
• RB25
• Locked diff
• 2 piece tailshaft

Problem info:

• October 2012 - Purchased car in QLD and drove it home to VIC (no apparent vibration present or I wouldn't have been driving it far)
• June 2013 - Raised the car and put new rims on to get it on club permit and drove it around a few times with no apparent vibration (from memory...)
• July/August 2013 - Drove it down the freeway and noticed a vibration from 70km/h and higher that shakes the entire car. It's so violent that the dash, seat and everything shakes so much that I have to slow down.
• September/Oct 2013
  • New wheels bearings fitted to rear due to play found in left hub
  • New rear tie rods fitted due to play found
  • New rear traction rods fitted due to play in stock items
  • Swapped rims for stock items (used the same ones for trip back from QLD) and also tried another set of wheels
  • Put rear on jack stands and ran it up to 70km/h and vibration is still there (eliminated it being a front end issue)
  • Removed tailshaft and ran up to 70km/h and no vibration present.
  • Got the tailshaft inspected and balanced and they said it was only SLIGHTLY out at the front and it wouldn't have caused a major vibration...still charged me $150 for the pleasure....
  • Inspected gearbox and engine mounts and they appear solid (only a mm or so of movement)
  • Refitted tailshaft and vibration is still there

Remaining options:

• Swap diff out for a stock item
• Others???

That's all I've got left at the moment - other than taking it to a workshop however based on previous experience I'm not super keen to do this - spend hours investigating, charge for it and the problem is still there

Any help would be greatly appreciated.

[SkudR33]

Hi all,

Been trying to fix this for over a month now so thought I'd create a thread on here to see if anyone has had something similar. I've tried to summarise as best as I could.

Car info:

• Cefiro
• RB25
• Locked diff
• 2 piece tailshaft

Problem info:

• October 2012 - Purchased car in QLD and drove it home to VIC (no apparent vibration present or I wouldn't have been driving it far)
• June 2013 - Raised the car and put new rims on to get it on club permit and drove it around a few times with no apparent vibration (from memory...)
• July/August 2013 - Drove it down the freeway and noticed a vibration from 70km/h and higher that shakes the entire car. It's so violent that the dash, seat and everything shakes so much that I have to slow down.
• September/Oct 2013

• New wheels bearings fitted to rear due to play found in left hub
• New rear tie rods fitted due to play found
• New rear traction rods fitted due to play in stock items
• Swapped rims for stock items (used the same ones for trip back from QLD) and also tried another set of wheels
• Put rear on jack stands and ran it up to 70km/h and vibration is still there (eliminated it being a front end issue)
• Removed tailshaft and ran up to 70km/h and no vibration present.
• Got the tailshaft inspected and balanced and they said it was only SLIGHTLY out at the front and it wouldn't have caused a major vibration...still charged me $150 for the pleasure....
• Inspected gearbox and engine mounts and they appear solid (only a mm or so of movement)
• Refitted tailshaft and vibration is still there

Remaining options:

• Swap diff out for a stock item
• Others???

That's all I've got left at the moment - other than taking it to a workshop however based on previous experience I'm not super keen to do this - spend hours investigating, charge for it and the problem is still there

Any help would be greatly appreciated.

I reckon it could be the diff on its way out - ford j used to own a few years ago, as it was on its way out it started to vibrate, sort of like a feeling of vibration to the left... Ended up being the diff's way of asking to be replaced.

Ps: I'm no professional so you should probably wait for a few people's opinions

[konect]

Vibration is still there...

• Removed the rear wheels and tightened the lug nuts on to hold the discs in place to 100% eliminate wheel issues.
• Swapped the diff last night for a stock r32 item
• Rechecked the gearbox yoke, centre bearing

Other possibilities:

• One of the rear drive shafts are dodgy - vibration definitely feels closer to the front though
• Gearbox has an internal issue of some sort that is only affected when the tailshaft is attached

Anyone know of a good driveline workshop on the Westside? I'm almost at the stage where I'll take it to a shop and say...

[konect]

Took it to the driveshaft place again and they suggested the alignment of the gearbox looks to be off due to a sunken mount.

Waiting on delivery of a Nismo gearbox mount and hopefully that fixes it!

[konect]

Gearbox mount replaced and it 'seems' a bit better but still vibrates almost as soon as I hit 70km/h >.<

No more ideas now...

[89CAL]

engine mounts? Centre bearing? Diff mounts/bushes?

I got a polyurethene gearbox mount and played around to get the exhaust hanger from the stock mount to fit but ended up with bad vibrations. Ditched it and it was fine. Probably not your issue but just putting it out there

[konect]

I don't use the exhaust hanger off the rear of the mount - was like this when I bought the car.

Engine mounts - Possible, but they look ok and without the tailshaft connected there is no vibration.

Centre bearing - Had it inspected when the shaft was out and is all good.

Diff mounts/bushes - Solid bushes all round and diff mounts are solid.

When I was test driving it last night it does feel isolated to where the rear of the box joins the tailshaft. I noticed that 2 of the bolts don't do up tightly on the crossmember so I'm going to tap them out to 12mm x 1.25 tonight and see how it is after they are fully tightened.

[89CAL]

Removing the tailshaft and running it up to 70km/h to me doesnt completely eliminate things in front of the gearbox as there is no real load on the engine.

Having said that, I pulled my engine recently and have been driving with a completely seperated left side engine mount, hadnt really noticed it

Fix the gearbox crossmemeber if you have an issue there. see what that does.

[konect]

Update...

• Revisted the driveshaft shop and they put it on the hoist again. They suggested the box alignment was affecting the angle of the front section and suggested I play with the spacing between the box/crossmembers and the centre bearing/body. Spaced the box up but no love.
• Ran the car with wheels off and touched various parts and the vibration is entering the body from the centre bearing mount (which I suspected from feeling the tunnel).

Plan for this weekend will be to replace the centre bearing and see how that goes. It feels solid and apparently is ok but there is almost zero movement in it and my research tells me that it should have some movement in there so I'll give it a go. The car was sitting for a while so its possible it has seized (no idea how old the bearing would be...).

If that is no good I'll consider a 1 piece shaft in the coming months but this may require an exhaust mod too.

[turboedsloth]

I don't use the exhaust hanger off the rear of the mount - was like this when I bought the car.

Engine mounts - Possible, but they look ok and without the tailshaft connected there is no vibration.

Centre bearing - Had it inspected when the shaft was out and is all good.

Diff mounts/bushes - Solid bushes all round and diff mounts are solid.

When I was test driving it last night it does feel isolated to where the rear of the box joins the tailshaft. I noticed that 2 of the bolts don't do up tightly on the crossmember so I'm going to tap them out to 12mm x 1.25 tonight and see how it is after they are fully tightened.

Solid diff mounts increase the amount of NVH throughout the car, i would be checking all the bushes in the back end and your diff. Grab the diff yoke and move it up and down, 1 of the pinion bearings starting to fail will cause a bad vibration also

[GTR-N1]

Does the vibration get worse if staying at a steady speed at 70 or above?

And is the vibration less if accelerating strongly through 70?

If you answer yes to both the above, I'd still suggest that the tail shaft is the culprit and thus, have a loan of another club member's shaft (that's alright). I had to replace my r33 GTR's shaft due to weakness in the middle.

[Gareth]

I have a similar sounding problem....mine is at 130km/h + doesn't sound as bad as your vibration though. seems as though mine originates from rear of gearbox/front of tailshaft. interested to know if you managed to fix yours.

[konect]

Vibration is fixed! Had a whole new tailshaft made but Melbourne Driveshafts and not an ounce of vibration is present now.

Interesting that even after being told the old tailshaft was balanced properly and had no visible issues it actually was the problem. M&S Driveshafts continued to tell me my gearbox was out of alignment and wouldn't test drive the car to see what the issue actually was.

Glad I ended up going somewhere else in the end

Edited August 17, 2014 by konect

[Gareth]

Thanks for the update! my vibration turned out to be one of the hicas rack ends, Chasers were trying to tell me i needed another new wheel bearing even though they had just been changed, reckoned they had been installed wrong (wasn't done by them).......pfffft, glad i didn't listen to them those OEM bearings and hubs are expensive.

[skylinekid_9]

im glad i found this thread

i have the same issues...

BUT.....

currently my gearbox is not aligned ( so i know i def need to get the gearbox mounts)

Was also told i need to replace basically all rear bushes so im trying to poly bushings all around

need to check if my mounts are all solid...

currently driving the cars is very harsh esp with it sitting on coilovers

[Gtr800]

Thanks guys, I'm going the thru same problems. Hopefully it's something simple to fix.

[BI6TIM]

I also have a similar problem with my r33. Since owning it, about 2 months now, I've changed diff, tail shaft and clutch and a vibration still persists.

My vibration is not as bad as what you described konect but it is enough for me to not drive the car on the highway or attend track events such as happy laps, which is very annoying.

I had planned to fit new wheel bearings to the rear and maybe rear tie rod ends or ball joints. I might now also look into gearbox mounts as the car came with Hardrace engine and gearbox mounts.

I'm very interested to here from others what was their fix.

This problem dampens the enjoyment of owning such a vehicle.