Drivetrain vibration at Highway Speeds

[510SSS]

Hi guys, now that I have diagnosed my pinging problem, I took it out for a test drive and as I was rowing through the gears I realized that as I got up into 4th or 5th and was over 50 mph, there is quite a noticeable vibration in the drive line, I cannot tell if it is wasd U joints, an unbalanced driveshaft, or maybe my engine needs a harmonic balancer? On top of that my Diff is starting to whine a little bit, I do not know if this is related, but maybe some chunks of the internal gears have sheared off or something. Anyone who has had a similar situation can give me any advice? Thank you.

[Draker]

How do you know it's not a wheel? If you think it's the drive shaft... go have it balanced. But you should prove it first. The diff won't cause vibrations. 

[MicroMachinery]

Sounds like an imbalanced wheel.

[Dolomite]

Check wheel balance, half shaft u joints, drive line u joints, rear suspension arm bushings. Sounds odd, but my buddy had an odd vibration at freeway speed, turned out to be suspension arm bushings.

[scooter]

vibration can come from anything that turns in your drivetrain. put oil in your diff and it will stop making noise.

[Doctor510]

Hi guys, now that I have diagnosed my pinging problem, I took it out for a test drive and as I was rowing through the gears I realized that as I got up into 4th or 5th and was over 50 mph, there is quite a noticeable vibration in the drive line, I cannot tell if it is wasd U joints, an unbalanced driveshaft, or maybe my engine needs a harmonic balancer? On top of that my Diff is starting to whine a little bit, I do not know if this is related, but maybe some chunks of the internal gears have sheared off or something. Anyone who has had a similar situation can give me any advice? Thank you.

Check ALL 6 of the U joints, L series 4 cyl engines do not need a harmonic balancer, that's why they didn't have one from the factory.  Diff could be whining because of lack of gear lube.

[datzenmike]

Look to see if there is a clean spot where a balance weight has fallen off a rim.

 

Inspect the tire by raising it and spinning while looking at the tread. Any lumps or bumps in the tread. Is it symmetrical?

 

Is there mud caked to the back/inside of the rim?

 

Swap the rear with the front tires. Did the vibration seem to move? It might start shaking the steering wheel. This would indicate that a tire or rim or both are out of balance. 

 

While the rear tires are off look at the drum. Is it damaged or missing any metal?

 

 

 

Inspect the drive shafts for a clean spot where a balance weight has fallen off.

 

Turn it by hand (with a wheel off the ground) Is there any dents, scrapes or damage of any kind on it?

 

Take drive shaft out and inspect the U joints.

There should be zero play or movement except turning.

Turning should be absolutely free with no tight spots.

Really lean on them to see if there is any slop. Are the C clips in?

Are the U joints centered and undamaged? 

 

If you have the slightest doubt about a U joint replace it or them.

 

 

If you have never changed the oil or do not know when it was changed last you may as well dump and replace it now. GL-4 80 w 90 for the transmission and GL-5 90w for the diff.

 

 

Now..... write this stuff down and when you have confirmed that something is ok check it off the list. They don't have to be in order but they should all be looked at. Do the easy and cheap ones first. Be methodical and this problem shouldn't take 10 pages to solve.

[scooter]

i just went through this. brand new driveshaft. vibrated like fuck, im not sure what i did wrong with the u joints but it vibrated badly and it cooked all the grease out of the joints, put new ones in again and now its smooth as a babys bum.. just has some light tire shake around 200kph now lol.

 

just cause they LOOK okay, doesnt mean they are okay. if the u joints have any play in them at all or squeak, or just plain look old and shitty, throw some new ones in...

 

has anything been changed lately? maybe a wheel is loose? with it being a 510 the driveshaft is probably fine if its not bent or dented.

 

harmonic damper isn't a bad idea on an all out race motor that's screaming all the time, but on a nearly stock l16,18,20b with bolt ons its completely overkill.

 

I have an ati superdamper on the front of mine, but it has a half counterbalanced z22 crank and sees 7500 often. AND IT KICKS ASS TO SET TIMING due to the laser engraved marks.

still probably overkill for my use but whatever.

 

DO as what mike says and you'll figure it out. don't be afraid to use a pry bar to see if it moves, a lot of force goes through those things.

[510SSS]

Ok thanks guys  I will check off the whole list one by one, I did notice there is some play in my differential no bueno. I do have some old ass tires so maybe that's it they might not be balanced, I just changed my rims out but decided to use my old tires anyways cause they had almost full tread left and I don't have mucho dinero. :angel: I will put it up on the lift and go through the U joints too, might be time to put in the LSD since im going through the U joints anyways I guess. Is it true that you can install the Subi r160 diff with the stock 510 half shafts and all? And you just need the new Subi seals right?

[datzenmike]

If you changed the tires onto different rims they should have been balanced then. If they weren't then this is most likely the cause of the vibration. Move tire balance to the top of the list. If they were not balanced get them balanced.

[scooter]

old ass tires.

[DISLEXICDIME]

The subaru r160lsd has to be from 91 or older

[510SSS]

K I figured it out guys my Driveshaft U joints were all shot to hell, causing a bunch of play in the driveshaft and it started to really cause vibration as I got up to higher speeds over 55 mph. Now since im changing U joints I am going to just put in the Limited Slip Differential, fresh Half Shaft U joints, and Re-balance the drive shaft all at once. I was wondering have you guys ever changed you're rear cross member? I wanted to get this done at the same time since everything is going to be apart anyways, can you guys recommend a place to source an aftermarket rear cross-member that is adjustable? Thanks all. :thumbup:

[datzenmike]

You should not need to re-balance a drive shaft that has already been balanced.... but they will be glad to take your money. Change the U joints and go from there.

 

Byron Meston  http://byron510@telus.net  of The 510 Realm makes a kit I believe. You'll have to check with him.

 

See: http://www.the510realm.com/viewtopic.php?f=10&t=6946&hilit=Byron%27s+adjustable+rear+crossmember

[510SSS]

Ya duh Mike, I was just thinking of doing it as a precaution if it became unbalanced from the heavy vibration, but I guess money is all life means to some people, not making their vehicles safe to drive. Anyways thanks Mike for the recommendation I will hit up Byron, was gonna do that anyway, just wondering if anyone knew any other companies that offered pre-built modified crossmembers as well? Thanks.

[datzenmike]

You take it in and say you want it balanced they will 'balance' it and tell you "wow good thing you brought it in" to justify the $200 bill. (they will also replace the new U joints too, try it and see) Talk about safety, that money could have gone towards brakes or tires.

 

I'm more "don't fix what ain't broken". Most certainly "don't throw money at something that ain't broken". Two U joints $60 and two hours work for yourself. Drive it... no vibration... problem solved.

[510SSS]

Ya im more of the push the project as far as possible type of guy I guess, not just throw duct tape on it. So im redoing all of my U joints, putting in LSD, Pentultimate crossmember, and adjustable front suspension, I think this should fix my drivetrain problems and help my car bump steer alot less. Thanks for the money saving tips tho mike, prolly a good plan too. 

[Stoffregen Motorsports]

A straight driveshaft needs no balancing. That's the rule of thumb I have used for years, but there are guys who think I'm nuts. Ask a driveline shop and they will tell you that I'm wrong, but guess what, they want to take your money and balance your driveshaft.

 

510's have an inherent vibration, especially when lowered. Installing CV joints on you half shafts is the only way to get rid of the vibrations. Adding an adjustable rear crossmember helps reduce the vibrations, but will not get rid of them altogether.

 

I had a '69 4dr once that had bad vibrations, and all of my attention went into the rear trying to locate the vibration, well, it was actually bad front control arm bushings. Never saw that coming. Point of story? It may be time to replace all the bushings. Cheaper to do it in one shot than over time.