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Drive Shaft Play into Transmission

Good evening, everyone -

Monday afternoon, I started to notice a ticking noise that sounded like it was coming from the front wheels when accelerating in my 04 Ford Escape XLT. It sounded sort of like I had a stone in the tires, as it would get faster with the car - the thing that seemed odd to me was that once I got up to ~10-20mph, the sound would go away. When I got home, I pried all the stones out of the front tires that I could find, checked them over for nails or bolts, then hopped back in and took a test drive around town - nothing. Slightly satisfied that I solved the problem, I forgot about it. Til today. On my way home this afternoon I was cruising with the windows down - I rolled over a small bump coasting into a stop light and just like that, the ticking was back. Out of pure curiosity, I went straight to my local shop. Their initial theory was that since it was coming from the wheels, it might either be a brake issue or a bearing issue. They took it for a test drive around town, then hoisted it up on the lift to take a look around. Both brakes and bearings were in great shape, but while they were looking around, they noticed that there was a decent amount of play in the drive shaft leading into the transmission. The guy at the shop said that in his opinion, the ticking was coming from the transmission/drive shaft. He told me that if that was the case, he didn’t see how the problem could be resolved without rebuilding the transmission. I’m dreading the thought of this - he admitted up front that he is not a transmission expert and referred me to a shop that specializes in transmissions 2 towns over.

If his theory is correct, will the transmission, indeed, have to be rebuilt, or could it be as simple as replacing the drive shaft and/or the U-joints? If I can get away with just replacing the drive shaft and/or U-joints, is this a complex, expensive job, or is it something that could be done in an afternoon in the driveway? I did a quick search before starting this thread, and someone posted an earlier discussion (very similar situation to mine) where the prevailing opinion was that the problem was with the car simply needed new u-joints.

I only drive the car twice a week - about 20 miles each trip, going no faster than ~55mph on back/city roads. Is the car safe to drive if the drive shaft is indeed a problem, or should I look for other ways to get around?

Thanks in advance!

I would strongly recommend that you get a second opinion. And if you take the car to a second shop do not mention that anyone else has looked into the problem.

Almost without question the driveshaft ujoints are dry and failing. If you remove the driveshaft and take it to a local auto parts repair shop they can replace them for around $100. Some might even take the shaft out for min charge if you can’t do it. Otherwise just about any independent shop can do the work. Shouldn’t be too expensive…

Thank you for the replies, Rod Knox and TwinTurbo! So in your opinions (and I know you are limited by not being able to lay hands and see for yourself):
1.) Is the car safe to drive to/from work (local roads, max 55pmh)?
2.) Would the transmission need any type of work as a result of such repairs?

Again, I really appreciate you input. FIL is an engineer for Ford, so was planning on having him take a look this weekend. Car has been running just fine, save for the ticking, which isn’t even consistant.

THANKS!

it could possibly be very dangerous. if your driveshaft drops and catches the pavement you could flip over. but as you said, we can t see the problem. I would find out ASAP. I m having a similar prob in my jeep, and I m not taking it out at highway speeds until I find out for sure what it is

A “stone in the tire” makes a “tick” once per wheel revolution. The drive shaft from the transfer case turns at about 3X wheel speed and would “tick” much faster.

Insightful, thanks for your reply. From where I was sitting, it sounded approximately like it was happening once per rotation, but I could be off. Either way, the sound went away (or at least became inaudible) at approximately 10-20mph. Not sure if the u-joint/drive shaft are the source of the noise, but the garage did say that regardless, they noticed a lot of play on the drive shaft.

Another clue is if the noise changes when you’re accelerating vs coasting or decelerating. A stone noise will not be affected. A drive-line noise would change.

Do you mean like a change in pitch? The pitch and tone of the noise remains constant as long as it is audible. The stone in tire theory has been debunked, though. Right now I’m a bit less worried about the actual original noise (though it does make me paranoid) as I am making sure the u-joint/drive shaft issue is safely resolved (ideally without a full trans rebuild like my mechanic originally suggested)

I mean frequency. Your truck’s tire has a 7.3’ circumference. At 7.3 feet/sec (5 mph) a tire/brake/half-shaft noise would occur once/sec. A drive shaft noise would be three times/sec. This difference is easily heard.

It may not tick every revolution. If its dry u-joint, it will tick as it binds up and sticks. They make a lot of noise before they go completely out. The end caps have large straps holding them on. It is safe to drive as long as you drive gently. Slower speeds are better of course. Don’t procrastinate, drive it to the shop as soon as you can.

Put your truck in park and slide under it. Putyour hand near the middle of your driveshaft and try to rotate back and forth. You should hear some noise and see some movement from either the front or rear u-joint.