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Sun Apr 15, 2012 8:48 am

OK, I have a 66 that is slammed. The rear axle nuts keep coming loose. It came loose enough one time to shear the drum splines and leave me stranded. I have replaced the rear bearings, brakes, drums, axle nut, and cotter pins(after I retighten each time). I use the torque mister tool to tighten the nuts. I apply as much torque as i can to the tool unit the nut just wont go anymore(full body weight on a breaker bar, on the tool) After a long day of driving you can feel a clunk when you grab the rear wheel and shake it(with car on the ground). The tranny and motor mounts are new too. Any suggestions??????

Sun Apr 15, 2012 9:37 am

First suggestion is to STOP using a breaker bar on the torque tool! Follow the directions and torque settings and don't try to exceed them!

The nut is supposed to be 250 to 275 foot pounds. By using a breaker bar and standing on that you are probably putting well over 1,000 foot pounds on the nut. Something is going to give!

And it might just be that you have over streesed the nut to the point that it is actually jumping over the threads to get loose. It can do that under extream loads and won't appear to be stripped.

You may also be compressing the drum to the point that it is failing which is giving you excess play making it appear the nut has come loose.

But that kind of torque is definately going to hurt things.

Running low puts a lot of pressure on the drums. Bad toe adjustment on the rear adds to that.

It may look cool to be running low, but no good can come from it. It's hard on everything from axles, fulcrum plates, drums, wheels and tires.

For some they are willing to pay that price for the look. Others, they don't want those hassles and expenses. You need to decide if the look is worth it to you. If not, raise it up some and many of these issues will probably eleviate themselves.

Sun Apr 15, 2012 10:09 am

I have accepted that there will be issues with running it low. I was just hoping that i wouldnt have to re tighten so often. I tried to follow the directions and they still come loose(. I'll go through it again and see what happens.

Sun Apr 15, 2012 7:22 pm

I can't imagine what kind of torque you got standing on a breaker bar on the torque tool.

I use a 3/8 ratchet and can easily over torque them with that!

Sun Apr 15, 2012 9:19 pm

I fully agree with the Doc! No matter what anyone tells you, running real low on back isnt good. I have personally had all kinds of issues as a result over the years. I personally spun a drum and walked 10 miles home, 1 hour after I re-tightened my nut. Major negative toe and negative camber will eat drum splines, especially cheap ones. Despite of the fact it looks cool to a point, I got sick of all that mechanical BS. I now run them with drop plates and dont run that as low as I used to.

You may not like the advice, but you only have three choices. Either raise the rear a couple notches and get some kind of drop plate to help toe, or keep spending money and time fixing broke stuff. The other choice is to only drive it once in a while and keep spare drums/nuts/cotters in the car. Age has taught me the latter aint worth it= especially when you cant spend the weekends or evenings with your wife or girlfriend because you a) ran out of money buying damn car parts and cant afford to take out the family b) have to work on the damn broken car instead of relaxing with the wife/fam; thus making you pissed on Monday since you were lucky and got to work on your day off!

Vws bust and fall apart on their own, partly due to age and cheap aftermarket parts. You dont need to purposely set the suspension up wrong and induce un-necessary damage further.

Personally, I like the whacking tools. They are cheap and work. Ive used the same one since 2001 and keep it in my car at all times, along with spare nut and cotters.

Mon Apr 16, 2012 3:56 am

Wonder what kind of shape your bearings are in and if that is related to your problem. You need tranny oil in there to lube them and with the axle up, you are getting minimal, if any oil to them........

Mon Apr 16, 2012 6:44 am

This is the first bug that i have ever lowered, all my other ones have been at stock height. I might try raising it an inch and hope for less problems. It is just an around town summer car. Thanks yall for the info, keep it coming if there is more to you have to add. The more you know ;)

Tue Apr 17, 2012 3:46 pm

I recommend raising the back enough to have slightly positive resting axle tubes (now they are negative), or at least get them to where they are on a dead flat horizontal axis with the gearbox. This is how mine is. You may need a set (or additional if you already have them) of caster shims for the front, if you raise the back enough to induce some rake.

Tue Apr 17, 2012 5:42 pm

cbatteryman wrote: I have replaced the rear bearings, brakes, drums, axle nut, and cotter pins(after I retighten each time).

What you have not replaced apparently is the axle shaft itself. I would wager a large sum of money that the splines on the axle shaft are sufficiently worn that even your new drum cannot be kept from a minute amount of shifting on the axle shaft and over time the shifting will loosen the nut.

Also a possibility is that you replaced the drum with a non OEM drum and that plus a worn shaft will not remain tight.

It takes a very small amount of wear on the splines to allow 10ths of millimeters of drum to axle rotation sufficient to prevent loosening of the axle nut.

Do a search for worn axle splines or drum splines and you'll have plenty of reading.

Wed Apr 18, 2012 10:53 am

I highly doubt it is the axle shaft. Those splines never go bad, it is the drum splines that go on slammed cars. That axle shaft strength is superior to the drum splines. My old bus that spun 2 drums never had any damage to the axle splines. I had incorrect drums for an IRS conversion, it wasnt that fact that they were not tight enough. A new German drum is VERY tight on an old axle.

I would guarantee 99% that raising the rear and putting German drums on back (new) would solve your issue with the drum.

Wed Apr 18, 2012 11:28 am

smitty24 wrote: I highly doubt it is the axle shaft. Those splines never go bad, it is the drum splines that go on slammed cars. That axle shaft strength is superior to the drum splines. My old bus that spun 2 drums never had any damage to the axle splines. I had incorrect drums for an IRS conversion, it wasnt that fact that they were not tight enough. A new German drum is VERY tight on an old axle.

I would guarantee 99% that raising the rear and putting German drums on back (new) would solve your issue with the drum.

We've repaired two "loose axle nut" problems for dune buggy customers by simply replacing the shafts and proper re torquing; same German drum, same nut, no height adjustment or camber change (other than checking it). The wear on the shaft splines was minimal but totally noticeable by eye.

Wed Apr 18, 2012 5:10 pm

cbatteryman wrote: I use the torque mister tool to tighten the nuts. I apply as much torque as i can to the tool unit the nut just wont go anymore(full body weight on a breaker bar, on the tool)
drscope wrote: By using a breaker bar and standing on that you are probably putting well over 1,000 foot pounds on the nut. Something is going to give!

Let's be conservative and say cbatteryman weighs 150lbs., and he's standing 18in. away from the nut on the tool, which multiplies it 9 times. He's putting just over 2000lbs of torque on that nut, assuming no losses.
And now for the puns...

That's a ton of torque
and
That must be a tough nut to crack.

Wed Apr 18, 2012 7:07 pm

That's a ton of torque
and
That must be a tough nut to crack. :lol:

Wed Apr 18, 2012 7:10 pm

torque that those parts were never supposed to encounter. I suspect nothing short of changing the axles and castle nuts will fix the problem.

Wed Apr 18, 2012 8:22 pm

The splines on my axle are worn down and i have to replace it. thats what im doing this weekend. I kept breaking drums

Thu Apr 19, 2012 8:38 am

I thought that it would be 1.5 x 150 since 18 inches is 1.5 feet. and its Foot lbs. I pry wrong but thats how ive always understood it.

Thu Apr 19, 2012 8:50 am

cmiller95 wrote: I thought that it would be 1.5 x 150 since 18 inches is 1.5 feet. and its Foot lbs. I pry wrong but thats how ive always understood it.

Then the torque tool is a 9 times multiplier. So 1.5 x 150 is 225. 225 x 9 is 2,025 foot pounds. So it's still over a ton of torque.

Thu Apr 19, 2012 9:16 am

andk5591 wrote: Wonder what kind of shape your bearings are in and if that is related to your problem. You need tranny oil in there to lube them and with the axle up, you are getting minimal, if any oil to them........

On my front hubs I found that the bearings were being torqued to much which wore them out. It then collapsed and clunked but the nut never moved. It took about a hour of driving to do that.

Is the cotter pin being cut off? If so that in itself is alot of pressure from just the nut coming off.

I bet the angle is causing the problem and is affecting your bearings. Nice slam though.

Thu Apr 19, 2012 11:43 am

I had a very similar issue keep occuring on a different car and I used RED loctite(yes I said red) with the proper torque spec. it has yet to give me an issue since.

Thu Apr 19, 2012 2:57 pm

I wouldnt use Loctite. It is not necessary or recommended. You do not need it if your parts are functioning and not wore out, proper suspension height, along with proper torque at the nut. The nut will keep itself on; the pin is a "just in case" precaution measure. The only time my nuts kept coming loose is when my axles were beating the splines of my drums out and the nuts would loosen as a result. Incorrect or very worn splines on drums also lead to this.

Magellan= is your car slammed or mild?