TR6 TR6 CV axles

[Guest]

This is a cross post from another site. I make no apologies, mainly because it's safety related. Also because I'm looking for a quick answer to a question.

<span style="font-style: italic">As many know, I have the R200 and CV axles. Installed by a mechanic that since went out of business.

They've got about 1600 miles on them. When they went in originally they were silent. Recently I've been hearing a clunk on startup, which sounded like the exhaust.

I'm taking a little 1500 mile trip next weekend, so I thought I'd have a little look at the back to make sure everything was buttoned down. Bit of preventative maintenance, dont'cha know...

Pulled the drivers side wheel and all looked good. Pulled the passenger wheel and it wasn't so good. There are 6 hex cap screws holding the CV axles to a spacer, and 6 9/16" nyloc bolts holding that to the diff.

All the nylocs were loose. Three of the cap screws were backed completely out of the spacer, and the others were all loose. God forbid they let go at 85 on the freeway.

Turns out the problem was twofold.
#1: The cap screws weren't loctited in when they went in.
#2: The diff wasn't mounted properly. Two out of the four mounts were loose, allowing it to rock.

I'm guessing that the rocking motion of the diff is what worked the cap screws and the nylocs loose. I've tightened everything down, including the diff, and loctited the cap screws - only blue, because that's what I had - and we'll see where we go from here.

So - if you have the CV axles, you might want to pop a wheel off and make sure the cap screws are loctited. If not, do so immediately.

Oh and on a personal note - the HF impact wrench was the best $10 I ever spent. It made pulling the wheels and tightening the diff a breeze
</span>

Now my question:
I already got a recommendation to upgrade the hex cap screws to 12.9 instead of the 8 they came with. I want to do the nut:bolt pairs at the same time. Because they are a bugger to get a socket on, I'm going to use hex head cap screws and nylocs. I know they are 3/8", I have them all picked out, I just need the length and I don't want to go jack the car up if I don't have to.

<span style="font-weight: bold">Does anyone know it? </span>
Remember this is the CV conversion, not stock.

 

[TR3driver]

Can't help with your question, just wanted to point out that there are much better locking nuts than Nylocs. I use the "oval lock, conical top" type from MMC on my driveshafts (no Loctite) and they never back off even in places where (new) Nylocs did.
https://www.mcmaster.com/#catalog/114/3139

 

[DNK]

Since I have joined this forum ,I have been interested in trying "metal Locks". I really like these things.

 

[LastDeadLast]

I use metal locks on all the u-joints.. They don't move. And after installing a drive-shaft your arms hurt.

-s

 

[Guest]

I concur on the all-metal locking nuts. I have very few Nyloc nuts left on my car, none on high-stress unions. Just remember that all-metal locking nuts are a one-use item. Do not try to reuse them and expect the union to be safe.

 

[Guest]

In a similar vein, I recently re-installed my roller rockers after re-torquing my head. I grabbed a handful of new nuts from my parts bin and torqued all 6 down to spec, 26-34lbs. 3 of the nuts stripped! What I grabbed was standard Chinese nuts. Went back with grade 8 nuts and washers. Remember too, that all locking nuts are not created equal (the valve train calls for standard nuts, not locking), referring back to original thread on this post. Make sure that what you buy are at least a grade 8 or better, you will have to go online or a specialty store, not Lowes or Home Depot.

 

[Guest]

McMaster-Carr. Best website out there for fastening things together!
I just have to find the enthusiasm to jack it back up to get the length of these bolts now and I'm all good.

 

[Trick6]

Alan:
Do you think the mechanic did not tighten everything or do you think the fasteners backed off?

You have called attention to the point that, if/when a mechanic does anything for us we should inspect it by getting under there and putting a wrench on it to make sure it has been locked down. Our lives could depend on it.

At the start of each season, and when I service the car, i.e., oil, filters change, grease, I put a wrench on drive train fasteners. I am always putting a wrench on something under there. It makes me feel good.

I am very happy that you discovered this before something failed. We all should listen to our cars and not just turn up the radio for "it to go away."

 

[Guest]

Al, the instructions I received from the mfr clearly said that these bolts had to be loctited.

The problem (I guess) was that the spacers had to be machined twice - the first set didn't fit and when he put them in the second time he either forgot or flat out didn't bother to put them in with loctite. Although when looking at them, they scream "threadlocker required".

The diff not being tightened up (which was the root cause of this) I'm more exercised about. But then it's hard to curse <span style="font-style: italic">at</span> someone who's not in business any more...

It's my own fault really. The car was in the shop so long that I got him to do a whole bunch of "might as well" stuff that I should have done myself. At least I rebuilt the suspension and brakes at home, so I know they are done right :wink:

 

[Trick6]

Alan:
I am in no way criticizing you. I first saw your excellent car at this referenced shop where I was having work done. I later discovered fasteners not torqued properly or tightened at all. I was also annoyed because of the lack of thoroughness or finish. Nice guy however.

This is for the benefit of this forum. We learn from what we all do, or have done, and share with one another. We enthusiasts need to check work done for us by others. Some mechanics just don't execute as we would and some others are very thorough.

See ya soon I hope.

 

[Guest]

Yeah, we won't talk about the rear hubs he "rebuilt" for a friend of mine. He said he had the correct tools to do it, and sounded like he knew what he was doing.

Turned out that his idea of the correct tool was a BFH. He bent the flanges, and the things had about 5x the runout they ought to have had. My friend was doing a resto and didn't find out until way later...

 

[crj7driver]

Alana,

Do you need the bolt size for the CV axles to the R200 differential adapter plate, or from the adapter plate to the R200 differential?

I am running a different differential but I think Kevin made the adapter plates off of the CV axles the same in all cases. If so I can get the bolt size on Wednesday when I get home.

Ryan

 

[Guest]

I had the size for the cv:axle plate. I needed the nut:bolt pair info - plate to diff. I went and measured it this morning. 1.5" x 3/8"

I'm going to swap to socket cap bolts - getting a socket on the bolts was impossible because the tolerances are too close. This will make tightening them so much more civilized. Lying underneath with 2 9/16" wrenches was no fun at all.