CB axels?

[Prince]

They're putting in the new brake pads as I type this, and I'll go pick the good old Maxima up in a couple of hours.

They told me on-site that I would need to have new "CB axels" put in. I took a look at them and for what I could tell he was right. The rubber part of each axel was broken, and the grease there was well on its way to being non-existent.

Can someone explain to me what these CB axels do, and what happens if I don't have them replaced fairly soon? The guy at the shop did tell me, but he used a lot of trade lingo, and I was too proud I guess to just say, "look, I've no clue as to what the hell you're saying".

I'll share this amusing bit with you, though. As I recently got married and the wife and I are newlyweds, and the car was bought for her by her parents, they've told us that in a way of helping us get started in life they'll pay for maintenance on the car. The thing is, their one and only condition is that I use OEM parts (Nissan) for all repairs. The old man is really determined about that.

Okay, that's fine, I can live with that! And with brake pads the difference in price is rather minimal, but I got quotes on these CB axels... And as it turns out, putting in new OEM axels will cost about 1,500 dollars, whereas putting in generic brand axels will total to around 360 bucks.

I wonder if her old man will still feel as strongly about using OEM parts?

[Peryn]

Well, for almost every application, you cant beat OEM for the best combination of durability, reliability, price, and performance. There are aftermarkets that excel in some of those, but OEM is almost always the only one good for all catagories.

OK, now on to CV axels. They are called CV, for Constant Velocity. You car is FWD i believe, so you have to get power from the engine/transmission, to those wheel. The CV joint is the part that does it. One end fits into the Transmission, and the other fits into the hub on your wheel. So when they tranny makes your car move, the CV transmits power to the wheel so you can go. Once the boot rips on it, it starts spray grease all over everything inside your wheel well. This is a bad thing, if nothing else cause it gets all greasy. Also, when there is no grease on the part anymore, it doesn't lubricate or cool it well. This means very shortly the part will overheat, warp, and wear out very rapidly. I have never seen one get so bad for so long that something drastic happens, but i imagine it will eventually freeze up on you, and the joints wont do their job.

If you want to understand their importance, its kinda nice to know how they work. There are two joints each serving a special purpose. Basically they are like this : Wheel --> Joint --> Long section of straight metal --> Joint --> Transmission.
The CV joint has to be able to move the wheels forward/reverse, and still be able to do this as the wheels turn. So the joint has to be able to rotate and turn side to side at teh same time. Also, as you car hits a bump the wheel moves up and down. This means that bar going from teh wheel to engine has to be able to get longer and shorter as it rotates, and turns with the wheels.

The outter joint by your tire, the one you probably saw with a ripped grease boot, is probably the most important one. It has a series of balls in a cage in there, and that is the joint that allows the shaft to hit those wierd angles when turning your tires and still be able to rotate. Kinda like a u-joint. The inner one basicaly has some more balls in a hollow shaft. As you hit a bump, they can move in and out, so the shaft can get longer or shorter as need be.

Now that i've thoroughly confused you... thats a quick lesson on what CV joints are, how they work, and what they do. Let me know if anything in there wasn't confusing enough, or inaccurate, and ill fix it.

[grumpyolddude]

Nice explanation, Peryn! Touched all the bases, with enough flair to fake the obfuscation!

Prince... Does your father-in-law have a bias against US workmanship? There are several remanufacturers doing a very good job on those drive axles. If he is, however, covering the costs, get the OEM shafts.

Have you heard of the Magnuson-Moss Warranty Act? Maybe you should show him this: http://www.granatellimotorsports.com/magnusonmoss.htm

[scrt69]

well, my 2 cents in this... do you need the whole shaft or just the boot? I know where i work, we can get just the boot for most of our cars. and believe me, it is a lot cheaper if you do. but as far as oem vs. aftermarket.....
not even worht it to get oem unless it is warranty. toomuch of a price difference...like oem = $600...a/m = $100

good luck..kinda late, but oh well

[Peryn]

do you need the whole shaft or just the boot? I know where i work, we can get just the boot for most of our cars. and believe me, it is a lot cheaper if you do

ieee..... i would be very careful about that. Unless the boot is freshly ripped and still packed with a ton of grease, that is a practice thats just asking for trouble. Sure it might fix the immediate problem, and if the customer is warned they will need the whole thing fixed reasonably soon thats one thing... but most of the time if the boot comes in ripped, the whole half shaft should be replaced.

[Prince]

The guy said it looks like the boot (both of 'em) has been ripped for a while, and not exactly packed with a ton of grease. So, I believe I'm gonna go with replacing the whole thingamabobs.

[lt1s10]

Lately we've been busy with a number of Hondas and Toyotas. We tend to use rebuilt axles unless our customer really wants OEM. It's a lot faster and an easier job to swap an axle then it is to change a boot, clean the joint, and repack it.

Boots are running about $20 a side and complete axles $60 a side but I can swap axles on both sides in half an hour. It takes me probably 30 to 45 minutes to pull one side, clean it, repack it, and change the boot. Pretty much the labor times makes it more economical to swap an axle for our customers.

And like it's been said already. It's a lot better feeling to know that the joint is clean and rebuilt. Especially if you are not sure how long the boot was ripped and the joint was without grease.

[shakran]

if he's willing to forego the OEM requirement, the aftermarket axles will work just fine. I get all my axles from Raxles and they work great. They generally last at least 80k miles or until I swap motors and need a different axle, whichever comes first