Hello all...

My Santa Fe is up to 145,600 miles and still running like a top but I have started to notice a 'thud' in the driveshaft when applying the throttle at speed. It happens every time I step on the gas pedal unless I'm extremely gentle with it and the faster I step on the pedal, the rougher the thud becomes. I believe there is excessive play in the driveshaft (or propshaft) and every time power is routed through it, the slack is taken up and it thuds when it meets resistance.

The car is a permanent all-wheel drive system with 60/40 power distribution. Any ideas?

 

U-joints?

 

What happens to the engine revs when it makes the thud? Do they go high temporarily and then go down after the clunk?

Also, does the thud happen no-matter what, even on the freeway at low revs?

 

It drives normally when I give it gas but I just get a 'thud' and I can feel it in the seat and floorboard. I did a little more searching and found a site that suggested checking the play in the driveshaft by putting the transmission in neutral and setting the emergency brake. I got a ton of play and could freely turn the driveshaft back and forth by at least an inch. My mom's RX300 is also AWD so I tried hers using the same criteria and it did not budge at all.

 

I watched the tach and the needle won't rise until after the clunk. It does it at any speed above 20 mph or so but won't do it (or can't be noticed) from a standing start.

 

My 330xi does something similar, except it only happens if I let off the throttle a bit, and depending how high the revs were when I let off will directly effect how hard of a thud. Then again I've heard this is somewhat normal for BMW's but I'm sure it's really not.

 

Similar thing happened to my old Jeep. Ujoints fixed it.

 

Engine mounts?

 

The prognosis is not good folks. The transfer case is on its way out and will be a good $3,700 to replace so rather than do it, we're going to take the old girl out back and shoot her.

She's been a fantastic car but at this point we're throwing half of its value into maintenance every year and it's time to stop. I drove a 2010 Santa Fe and really liked it so I'm going to work things out with dad and see where we'll wind up.

to the Santa Fe and

 

Sorry to hear. Gonna trade it in? I know you take care of your vehicles, so if you want to sell it, it may be worthwhile picking up a used case from a wrecker and installing it to get maximum value for the car.




Terry

 

One of the techs at the dealership expressed an interest in buying it. Not sure when I'll get the new car but it will probably be very soon.