Dear Tom and Ray: The transaxle differential bearing on my '98 Toyota Sienna van is growling like a cat in the vet's office. This has been going on for about 5,000 miles now. Lately it has become more intense -- just like the cat does when the vet starts messing with his private parts. So far, we've dealt with it by turning up the volume on the radio. When it finally breaks, what will happen? Are we looking at a crash and burn -- or will I be able to drive it home? Any predictor of how long I have? Money is tight -- the longer I can prolong the repair or replacement, the better. -- Mark

TOM: Just before it breaks, it'll make even more noise, Mark -- so much noise that it'll sound like the cat is messing with the VET'S private parts.

RAY: At that point, most people become too terrified to drive the vehicle. But based on your letter, Mark, I'm not convinced you have that normal, healthy self-preservation instinct. So we'll tell you what happens if you actually drive it until it breaks.

TOM: What will happen, most likely, is that the differential housing will break and all of the fluid, and some of the gears, will pour out. And that housing is shared with the transmission. So the transmission and differential will fail catastrophically and simultaneously.

RAY: So the answer is no, you will not be able to drive home. Or anywhere else.

TOM: At that point, you'll need a rebuilt transaxle, which costs about $2,000. And since the subframe needs to be removed in order to get at it, labor will run you another grand or so.

RAY: But it'll cost just as much to fix it now as it will then. So if you can stand the noise, and can live with the risk of being stranded, you can just turn up the radio and keep driving it for a while until either your financial situation improves or your differential situation deteriorates.

TOM: I suppose you might consider flushing out the transmission fluid. That won't repair the damage that's already been done, but it might remove any metal filings that are now floating around in there and threatening to damage other pieces.

RAY: Yeah. I'd recommend that. It might buy you a few more weeks, Mark. Good luck.