Clunk/Thud Sound

[Lakitu]

I have a brand new 2017 Toyota 86.

I can't remember if the car has always done this since it was at the dealership, and I've had this car a little over a month. Just a little concerned with this clunk/thud sound that happens when I move the shifter gears from neutral to 1st, and 1st to 2nd. The noise disappears as I get higher up in gears. It almost sounds like its coming from the back of the car.

Does this happen to anyone else or did I already break my new car somehow? Or am I overreacting? I drove it off the lot at 4 miles, car now has 1800 miles as daily driver 2-hour work commute per day, beginner at manual)

I found an article of a Mustang guy having a similar issue, didn't really get peace of mind from that article though. I found a 8-year-ago Yahoo answers article where everyone pretty much said it was U-joint but thats so old it may not apply to me. Need extra confirmation.

https://www.edmunds.com/ford/mustang...unk-sound.html

[gramicci101]

An easy way to see if it's the u-joint is to grab the driveshaft and try to twist it back and forth. If there's play in the u-joint it might be bad. Your car is brand new, so unless it came from the factory with a defect, this probably isn't the case. Note: don't do this while it's spinning.

More likely, it's the diff flexing on its bushings, which are pretty soft and allow for a lot of movement. Whiteline makes inserts that take some of that compliance out, at the cost of a little more NVH.

Even more likely, it's the gear teeth in the transmission getting to know each other.

[humfrz]

^ ......yep, most likely just needs some more break in time.

However, you may wish to check the transmission and differential oil levels.


humfrz

[8RZ]

Is this your first RWD car? Just sounds like the diff, which is normal.

[Lakitu]

This is my first manual car, and first RWD. What do your cars do when you change gears? Is there any noise?

Also, one other thing, if I have air, I notice that when I have the AC running, I can smell some kind of strange smell, its almost like... best I can describe, a light scent of "old waterlogged cabin wood" coming through the vents only when switching from 1st to 2nd gear. This can't be the clutch, right? Not sure if it's still just related to needing to keep breaking it in. I figure the car must be fine, it's way too soon to be having problems! I don't know why, I'm just worried for no reason probably.

[8RZ]

That scent sounds lovely, actually. Normally I would suggest you change the cabin filter for any AC-related smells but your car is new, so it could still be burning off some factory fluids.

Yes, in my last 2 RWD cars I would get a thud sound when shifting from N to 1st from a stop. Maybe you could go back and test drive another 2017 to compare.

[radroach]

Google search : "ft86club rear end clunk" should give you the right explanation

It's normal. I'm pretty sure its a rotating shaft that you're bringing to a sudden stop when putting it in 1st. Wait 2-3 seconds when coming to a stop with clutch in to allow the shaft to slow down and it won't clunk.

[Tcoat]

Originally Posted by Lakitu

This is my first manual car, and first RWD. What do your cars do when you change gears? Is there any noise?

Also, one other thing, if I have air, I notice that when I have the AC running, I can smell some kind of strange smell, its almost like... best I can describe, a light scent of "old waterlogged cabin wood" coming through the vents only when switching from 1st to 2nd gear. This can't be the clutch, right? Not sure if it's still just related to needing to keep breaking it in. I figure the car must be fine, it's way too soon to be having problems! I don't know why, I'm just worried for no reason probably.

As said it is just the drivetrain taking up the slack in the lower gears. Perfectly normal. If you are burning the clutch you will have no doubt. It smells horrid.
Relax and drive. You will get used to the weird noises a lightly soundproofed RWD MT car makes. Then when it stops making the noise you will start to worry!

[Lakitu]

Originally Posted by Tcoat

As said it is just the drivetrain taking up the slack in the lower gears. Perfectly normal. If you are burning the clutch you will have no doubt. It smells horrid.
Relax and drive. You will get used to the weird noises a lightly soundproofed RWD MT car makes. Then when it stops making the noise you will start to worry!

lol. Thank you!

[SLVRSRFR]

Funny noises and funny smells are normal in a brand new car for the first couple of thousand miles especially.

I work at a dealership, and pretty much every new car emits a slight "burning" odor after a test drive, as the seals in the engine are still breaking in. It's made a couple of clients panic before, thinking the car was on fire.

But yes the thunk sounds like normal operation for a RWD car differential. Nothing to panic about.

[demasrv]

This is normal and you have nothing to worry about.

[stevesnj]

I have a Landcruiser with 2 solid axles and 2 driveshafts with a large transaxle between them. We essentially have the same setup. Gears driving 2 shafts at the rear though.

[shellslinger]

Normal. Nothing to worry about. Mine clunking and thuds went away eventually. I think it was either broken in or I changed fluids to Motul.