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Urghh.. Knocking in the rear

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Old 04-23-2004, 10:50 PM
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Ben Plaisted
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Default Urghh.. Knocking in the rear

I checked the archives and my symptoms aren't ( I don't believe anyway) like the symptoms for cv joints. The knocking comes only when I'm going slow like say 10-20 mph and let off the gas. it goes away when I get back on the gas. No knocking when turning. Any suggestions? Of course it starts doing this when I decide I'm going to try to sell. I think she hates me.

Ben
Old 04-23-2004, 10:54 PM
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Yup she found out you were selling, You have to whisper around them you know. There is not much back there but the transaxle I am afaraid..... Have you flushed and filled the Oil recently?
Old 04-23-2004, 11:00 PM
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Ben Plaisted
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transaxle oooh I hope not. Is it easy to flush and fill the tranny oil. Wheres the drain plug? I'll check clarks garage. Any other sugestions?
Old 04-23-2004, 11:03 PM
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83na944
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Yep, try changing the transaxle oil. Its about the simplest thing you can do. Better to start with the easy stuff.

The CV joints on my left half-axle got so bad that I could feel them binding. Sort of like the car was being held back and released. Also a knocking noise. It was worse when turning. The CV joints were really worn.
Old 04-23-2004, 11:09 PM
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Ben Plaisted
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Well I read clarks garage on changing the trans oil and sounds pretty easy. So I'll do that first when I get a chance. So if that doesn't work then check cv joints.
Old 04-23-2004, 11:14 PM
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tod84944
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This is a patch, but try flipping each axle around. In other words, on take a axle out, put the end that was on the tranny, on the wheel side. Might want to pack some extra grease in there while you are at it.
Old 04-23-2004, 11:23 PM
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Ben Plaisted
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Well I just went out for a quick spin around the block and I dont know if its good news or bad but I dont think its the cv joints/boots because the knocking only happens when I'm in gear so... I'm either screwed or the tranny fluid change will help. I hope
Old 04-23-2004, 11:25 PM
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The hardest thing about the oil changing, is finding a Hex wrench big enough to fit the plug. I bought a whole "big set" of allen (hex) wernches at Northern for around 15.00.
Good luck.
Old 04-23-2004, 11:39 PM
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83na944
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Remember to take the fill plug out first. If you can't get that out, don't drain the fluid.

I bought a single allen wrench to fit the plug at NAPA for about $5. I think its listed as a VW tool.
Old 04-23-2004, 11:46 PM
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Mike C.
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Could be a rear wheel bearing too.
Old 04-23-2004, 11:47 PM
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Ben Plaisted
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That makes sense, it would suck to drain it and then not be able to fill. I can buy the fluid at any auto store right? I'm thinking Redline MTL. Will it be a horrible thing if I can't get to this until thursday? I do alot of driving say like 300 miles by then.
Old 04-24-2004, 12:10 AM
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Redline might be hard to find. I found one place near Atlanta that had it in stock and another place the normally carried it, but was out. And Atlants is a big place. Alternatively, you can get the gear lube that the owner's manual lists about anywhere. I think its GL-5, but it might be GL-4 so you should check it.

You need to know whether you have a LSD to decide on which fluid you need. I use Redline MT-90 in my 83 LSD, and I really like it. Redline for Non LSD is 75W90NS, IIRC.

I doubt another 300 mi will hurt it, but you really can't be sure until you determine what it is.
Old 04-24-2004, 01:47 AM
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robthe54
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have you looked under the car yet? it's very possible that one or both of your cv's have loose bolts

when was the last time things got serviced back there?
Old 04-24-2004, 06:16 AM
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Ben, I had the same symptoms. It ended up being the CVs in the rear, the bolts were walking out, so I re-torqued them and was good to go. I also remember the same sound when my rear sway bar was overstressing and the bolt walked out on one side and the bar was knocking against something.
Old 04-24-2004, 08:46 AM
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Mr. Avionics
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Ben,
I'd check the CV's first, they can cause some strange problem symptoms. Just repacked mine, Whew was that a messsy job. Also replaced the tranny oil, used "Mobil 1 Synthetic, 75W-90" WOW did that ever smooth out the shifting, I was amazed at the improvement. Good luck and hope it is something simple,
Bill


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