My sons baja has developed a horrible knock from the rear which doesn't go with engine speed nor vehicle speed. Initially I thought something had come loose in the rear drums but all there was fine. Next thing was the CVs but they seem fine as well and so were the wheel bearings. I took out the gearbox thinking something loose inside, took that apart but that was OK too. The shocks are new and the bushes are fine and my son is quickly running out of patience with it. The only things left as far as I can see is the torsion bar bushes or the diagonal arm bushes. Everything feels tight as and the diagonal arm bushes look fine. The car is a 1968 baja with EJ22 engine , irs suspension and the noise is an erratic clunk not necessarily with bumps in the road but with me in the back with my ear to the floor (not easy I can tell you!) it seems to come from the passenger side rear from around the area of the torsion tube, could the torsion bushes be the wrong type? I believe without looking they are the doughnut type inside and the knobbly sort on the outside. Barry
if the torsion donuts are poly maybe one has split / shattered?
What about the bushing where the IRS joins the body?
The doughnuts are black rubber and so are the irs bushings. I'm thinking possibly the springplate maybe causing the noise now, it has been notched and may well not be notched enough but will look into that later.
Hey Barry I would double check cv's as its type 1 and not type 2 by memory. My type 2 cv's made sounds before I raced prepped/polished them so type 1 maybe screaming for mercy. The higher you go the more cv issues!
Have you checked where the torsion bar tube attaches to the chassis hasn't broken that bracket?
Well so far the gearbox has been pulled apart and nothing wrong there ( on the plus side pulled apart the ssp gearbox and found a chewed up reverse gear!). CVs appeared OK and the drive shafts, pulled the torsion bar cap off one side and that looked like it had been stuffing up where the springplate/torsion bar had been grinding on the cap. Just put it together, got a hundred metres from the house and bang, clunk etc! GGRRRRR!! It sounds like a metal rod is being pushed into the spokes of the wheel and that the wheel is about to fall off, whenever I've had cv issues in the past it has always sounded like ball bearings clicking against one another, agreed I've not had that on a raised baja before. Our next investigation calls for a Gopro to be stuck underneath to see if there's anything we can see! Update later.
could it be something to do with splines on the drum?
It's a new drum plus the brakes were the first thing I checked as to me it sounded like the internals of the drum were loose inside.
OK = drum is new but could the spline on the axle be shagged?
Well we've been down the end of our road and back and I wouldn't want to drive it any further. The video showed us nothing, the cvs went round and round but the sound was like a load of loose bolts in a tin can but only every so often not all the time. Michael is leaning towards CVs but at $140 a piece and no guarantee it is the CVs at fault I'm trying to stop him jumping the gun! The trailing arm bushes will be my next stop although I can't really see that being the problem and the only other thing I can think of is that the torsion bar tube itself maybe cracked, I'm hoping that's not the issue.
Axle splines are fine.
Keep looking Barry
I fold
Well, we looked at the videos - nothing! Pulled the diagonal arms apart - nothing, all fine. Checked the torsion bar tubes just in case I could see a crack, still nothing. The only thing left is the CVs but Michael has had them off and he reckons they're fine but they are now the only parts left that I haven't looked at and for this to start suddenly and the racket they cause just doesn't seem right. I drove the car myself from my place to Kunda Park (about a 45 minute drive) to get the Blue plate and back again, no noise. Michael drives it the following morning and this and as I said earlier my experience with CVs is clicking not a noise like a wheel is about to fall off or a drum about to self destruct!
1. Shock absorbers -- (or their mounting rubbers, bushes, or brackets.) "New" doesn't mean they can't be faulty... A very small gap, or
looseness in mount, can cause an unpredictable noise. [And who knows what a internal looseness/defect in a shocker could sound like...] Or are they
"topping out" if susp. is raised too high?
2. The bearings each side of the gearbox (between CV and diff., on side of 'box) can become loose/broken -- rare perhaps but it happened to me once.
Suppose you've checked those (and front mounting) -- as you have removed & pulled the 'box apart?
3. Rear axle nuts done up TIGHT?
All of those things have been checked and rechecked every time I've been under the car, had a wheel off and when the engine and gearbox were out. It has to be the CVs as they're the last thing to be pulled apart (by me) although it sounds far worse than a CV to me. The car drives nicely in all gears, changes fine and the suspension feels as well as a raised suspension can but the noise just doesn't give much confidence that something drastic is about to happen!
Well the CVs have now been replaced put back in, down the road and clunk,clunk bloody CLUNK! Nothing at all is loose at all. I found a crack in the rear bodywork near to where the rear body mounts to the suspension and thought that could be it. After a lot of swearing (mainly by my son!) he welded the crack, another trip down the road and clunk,clunk,clunk . He feels it is something in the gearbox but I had that apart and all was fine. I have no idea now, he wants to burn the car to the ground. It almost sounds like the gearbox mount but with the straps etc there is no way the box can move. I am all out of possibilities but the sound is so obvious it seems like it should stick out like dogs b*lls! It sounds like a rod is loose and banging on the floor.
$50. delivered to Taree. End of problem.
Seriously have you checked the front transmission mounting bracket,they often break loose.
Checked that and that's fine. I'm at a loss!
Maybe if you can record the sound and post it here, it might help others to narrow down what the cause is for you.
Yogie
I may have to do something like that. We've just taken the rear drums off and rechecked everything, nothing loose nor hanging off, put back together again then not even out of my drive and there it goes again. I had the idea off putting one of us in a trailer on the back and going down the road with the one in the trailer trying to pinpoint the noise! This was only slightly less dangerous than my sons idea of someone (him) laying on the car creeper underneath the car going down the road! Even though I've pulled the gearbox apart and it all checked out OK it's starting to look more and more we've got a duff one!
From the sounds and what has been said, I would put money on either suspension or gearbox.
We know it's the suspension or gearbox, the problem is finding it, everything has been pulled apart, some of it twice!
To me Barry, if your definitely sure its not cv's it must gearbox! It wont be broken body, engine mount or anything like that I recon! Something must
be binding under load and going bang. Casey started to explain what it will be in gearbox to me but we got interrupted by someone yelling, "you want
a beer". Ring him as he retired now and will probably shoot over to your place. I'm super busy for the rest of the week and Saturday.
We'll find it ! Cheers
I would possibly guess axles, as I had a friend who had a baja with the same problem, It turned out to be the axle gearing/teeth in the drum starting to wear down and slip.
If it were the gearbox as you say Shane, wouldn't you feel the clunk while driving? As it is the car drives fine, engine runs fine, no feel of a clunk just the noise. If it is the box then Michael will go spare as that's the shebang out again and I don't think he's mentally up to that. Btw I drove it from my house to Kunda Park and back with no trouble or noise, it was just the following morning when he drove it the noise started.
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The handbrake cables aren't seized even partially and the side gears were checked when I had the box apart. The above mentioned Casey will pop around this arvo so we'll see if he has any better ideas than me.
Well, the upshot of Caseys' visit is we're going with wheel bearings even though he and I have never heard a noise like this coming from a VW. Wheel bearings have been ordered so fingers crossed. Oh yes guess who's going to be doing the job, not my son!