2002 IS300 drivetrain popping

One of the advantages of a dealership's service department is that they are current on factory training, something that is not offered to non-franchised service operations.

It is difficult, if not impossible, to diagnose a noise without actually hearing it. The rear axle on a rear wheel drive is connected to the transmission by a driveshaft. At each end of the driveshaft are universal joints that allow veretical movement of the rear axle. A little free-play is normal, and there should be a factory specification in the factory service manual for how much is acceptable. If the universal joint is too tight, the vehicle can shudder at takeoff.

At 70,000 miles, it is unlikely that the U-joint is bad, unless the car was really driven hard.

Another possible source of metallic popping or clicking noise is aftermarket brake pads. If the backing is smaller than the factory spec, they can shift up and down, and when the backing contacts the edge of the caliper, you get a noise.

Thanks Mark and Ray for your comments! I am pretty sure it is not the brakes. As I mentioned when you rock the rear wheels gently back and forth you can see the play in the place where the long metal rod meets a junction near the rear wheels.

______________ |-----------------------| |-----------------------| | _____________| | | ____ =============================#===== |____| CLICK | | |-----------------------| |-----------------------| | _____________|

Here is a little diagram of the shaft and rear wheels. The clicking and play is most certainly coming from the spot where I've written "CLICK" and marked at the joint with the "#" mark. I stood under the car and hear it. I'm almost positive it is not the brake calipers.

Praveen

PS: How do I set my account such that it doesn't display my email address? 8)

______________ |-----------------------| |-----------------------| |_____________| | | ____ ==============#===== |____| CLICK | | ______________ |-----------------------| |-----------------------| |_____________|

I put up the diagram again as the previous one got messed up. I also made a typo in my first post. I meant that when he put the car up on the lift to look under it, we saw the play and clicking in the driveshaft that comes from the front to the rear and connects to a joint near the rear wheels.

As I mentioned, the sound and play is positively noticeable in the area in the diagram with the "#" sign and CLICK written.

Thanks again for your comments! What do you think?

Praveen

I put up the diagram again as the previous one got messed up. I also made a typo in my first post. I meant that when he put the car up on the lift to look under it, we saw the play and clicking in the driveshaft that comes from the front to the rear and connects to a joint near the rear wheels.

As I mentioned, the sound and play is positively noticeable in the area in the diagram with the "#" sign and CLICK written.

Thanks again for your comments! What do you think?

Praveen

I put up the diagram again as the previous one got messed up. I also made a typo in my first post. I meant that when he put the car up on the lift to look under it, we saw the play and clicking in the driveshaft that comes from the front to the rear and connects to a joint near the rear wheels.

As I mentioned, the sound and play is positively noticeable in the area in the diagram with the "#" sign and CLICK written.

Thanks again for your comments! What do you think?

Praveen

I put up the diagram again as the previous one got messed up. I also made a typo in my first post. I meant that when he put the car up on the lift to look under it, we saw the play and clicking in the driveshaft that comes from the front to the rear and connects to a joint near the rear wheels.

As I mentioned, the sound and play is positively noticeable in the area in the diagram with the "#" sign and CLICK written.

Thanks again for your comments! What do you think?

Praveen

I think you are much better at ASCII art than I'll ever be!

You asked in another post how you hide your e-mail address. I do not consider myself to be a computer expert by any stretch of the imagination but if you want to make it less obvious on the return address and you are using Outlook Express, go to the tools menu, then newsgroups, then click on the appropriate account, and fix your return address. Computer geeks will say that Outlook Express is bad and should not be used for reasons that are beyond my comprehension. I personally am willing to barter knowledge - I fix my computer geek friends' cars, and they make my computer work.

Back to your car question - your artwork indicates that it is the rear universal joint that is making the noise. As I mentioned before, some noise is OK, too much or too little is bad.

Thanks Ray! Actually, when I reread your reply, you did answer to the point what the problem might be. It is most probably due to the play in the universal joint nearer the rear wheels. As you mentioned, too little or too much is a bad thing. I convinced the owner this morning to let me take the car to another auto shop for a second opinion. So, Friday morning is when I get the inspection again. I don't mind spending the $70-$80 again. I just wish they had allowed me to take the car there in the first place.

I don't post using Outlook. I just post on the website directly and so I guess I can't hide my address. The email address is contaminated with junk mail already and so it's too late anyway :-)

I use Outlook for my work email and I don't really like it but I'm not really a geek and I can't articulate why I dislike it beyond the fact that it is slow and the options for searching your email messages for stuff are primitive.

Praveen

Also, if the play is too much, what needs to be fixed/replaced? Is it an expensive job?

Thanks!

If the play is too much, the driveshaft needs replacement. I've never priced a driveshaft replacement, but I would imagine that it costs $500 or so at a Lexus dealer.

Check the powertrain warranty on the car. If it has the same 72 month,

70,000 warranty as current models have, it may still be covered by the powertrain warranty.

Wow! And $500 is parts+labor? The car has just covered 70K miles. SO it looks like I've lucked out big time if it does require replacement. :-(

$500 is just a guess on my part.

In all likelihood, the universal joint and driveshaft will be within factory specifications and the car will be fine.

Thanks Ray! Keeping my fingers crossed.

Praveen

You're welcome and good luck!