Transmission Clunk

[Metalman]

This morning I came off the highway and did my normal flick the trans in manual and pull down through the gears as I am braking. I notice the tach went to idle when it showed 5th and then it went clunk into gear hard. Is this a sign that the trans is on the way out? Earlier this summer I had a check engine light that turned out to be the pressure switch in the trans code. The dealer reset the computer and it has been fine since. The car has 108000km and no the fuild has not been changed. I have had the car since 69000km.

 

[Metalman]

This morning I came off the highway and did my normal flick the trans in manual and pull down through the gears as I am braking. I notice the tach went to idle when it showed 5th and then it went clunk into gear hard. Is this a sign that the trans is on the way out? Earlier this summer I had a check engine light that turned out to be the pressure switch in the trans code. The dealer reset the computer and it has been fine since. The car has 108000km and no the fuild has not been changed. I have had the car since 69000km.

Its a 2012 with V6

 

[Cali Gen]

This morning I came off the highway and did my normal flick the trans in manual and pull down through the gears as I am braking. I notice the tach went to idle when it showed 5th and then it went clunk into gear hard. Is this a sign that the trans is on the way out? Earlier this summer I had a check engine light that turned out to be the pressure switch in the trans code. The dealer reset the computer and it has been fine since. The car has 108000km and no the fuild has not been changed. I have had the car since 69000km.

Well this is also an auto and engine breaking using the 8 speed trans is literally like saying please blow up.. use your brakes or go buy a manual. Im willing to bet if you do this often your the one thats destroying the tranny.

 

[Sthompsonmv7]

Well this is also an auto and engine breaking using the 8 speed trans is literally like saying please blow up.. use your brakes or go buy a manual. Im willing to bet if you do this often your the one thats destroying the tranny.

The car is controlled by computer and shouldn't let you damage it by up shifting or down shifting.
Mine does the same with not up or downshifting smoothly. My trans was shot! Pressures were good but no movement at all in gear. I replace the fluid with hyundai's 14$ a quart shit along with their filter/pan because the filter is built into the pan. Put lucas in it nd it is much better but not as good as new.

 

[Cali Gen]

The car is controlled by computer and shouldn't let you damage it by up shifting or down shifting.
Mine does the same with not up or downshifting smoothly. My trans was shot! Pressures were good but no movement at all in gear. I replace the fluid with hyundai's 14$ a quart shit along with their filter/pan because the filter is built into the pan. Put lucas in it nd it is much better but not as good as new.

Ohhhhhh ooookkkkkk LOOOOOOOOOL

 

[Sthompsonmv7]

Well this is also an auto and engine breaking using the 8 speed trans is literally like saying please blow up.. use your brakes or go buy a manual. Im willing to bet if you do this often your the one thats destroying the tranny.

I like to to down shift here and there. But if you put it in sport mode it does a decent job of holding gears out longer and also downshifting quicker.

 

[Cali Gen]

I like to to down shift here and there. But if you put it in sport mode it does a decent job of holding gears out longer and also downshifting quicker.

Whats sport mode? Is that also something that you can use incorrectly but it doesn't matter because computers will stop your car from breaking from improper use?

 

[amartz]

The car is controlled by computer and shouldn't let you damage it by up shifting or down shifting.
Mine does the same with not up or downshifting smoothly. My trans was shot! Pressures were good but no movement at all in gear. I replace the fluid with hyundai's 14$ a quart shit along with their filter/pan because the filter is built into the pan. Put lucas in it nd it is much better but not as good as new.

Really? You seriously think that? The computer may prevent a shift that would outright blow the tranny, but manually shifting it down? That is going to seriously shorten the lifetime of the tranny. Replacing brake pads is a *whole* lot cheaper than a new tranny.

 

[fourthirteen]

Replacing brake pads is a *whole* lot cheaper than a new tranny.

I’m with amartz on this. Cars are designed to be slowed by the brakes thus the brake pads are an easily replaceable wear item. Sure, engine computers will prevent a destructive downshift but using the trans to slow the vehicle is not really its intent.

 

[EdP]

I’m with amartz on this. Cars are designed to be slowed by the brakes thus the brake pads are an easily replaceable wear item. Sure, engine computers will prevent a destructive downshift but using the trans to slow the vehicle is not really its intent.

Well, sort of. The engine is really doing the braking, not the transmission. Of course it does put some force on it.

I'll agree it is not something to do all the time.

Engine braking is good practice in slippery conditions or going down a long hill. Dropping down one gear is not going to be a problem but I'd not drop down so much that it would near redline the engine.
On a very long hill you can do some damage to the brakes by overheating them too. Moderation and sensibility is key to safe driving.

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[amartz]

Well, sort of. The engine is really doing the braking, not the transmission. Of course it does put some force on it.

I'll agree it is not something to do all the time.

Engine braking is good practice in slippery conditions or going down a long hill. Dropping down one gear is not going to be a problem but I'd not drop down so much that it would near redline the engine.
On a very long hill you can do some damage to the brakes by overheating them too. Moderation and sensibility is key to safe driving

I agree totally on downshifting going down long hills. Like coming down the mountain from Boone in NC! And I will switch to manual to prevent the trans from shifting up gears if I know I'm about to let up on the gas and slow down for a stop-light, for example. But I *never* manually shift down thru the gears as I stop. Every time the transmission "thunks" into a lower gear, you've just put wear and tear on an expensive piece of equipment. It's good practice with a manual trans if you feather the clutch, and/or double-clutch to match up engine revs, but never with an automatic. They're just not built for that.

 

[Sthompsonmv7]

Okay, im not a transmission expert but today's transmissions with the computer controlling it will not let you do excessive damage. It won't let you go into 1st at near recline. Or anything close to that. Our cars paddle or manumatic is garbage it really doesn't do anything productive except yes.. keep you from going faster down hill due to the ratio of the gears. Our cars are a 6 speed with 2 overdrive gears. If you shift between the last 2 gears meaning 7 and 8 it doesn't do anything bad.
I would even say down shifting while you are breaking isn't horrible. The car will not let you go into a gear out of the parameters it doesn't like. I mean yes a little wear and tear. Okay... the car does the same thing in sport mode though. Revs are longer and down shifts quicker to a stop.
Also our cars are quickest after you have hit the gas in excess after a few times. The car learns that you want to-go FAST. It acts accordingly. Like I said I don't know cars. I was only a mechanic for MBZ and I am good friends with a dealership mechanic.
They broke off to genesis for a solid reason. They are going after the big dogs. You can't sit there and tell me downshifting your car our cars is really that bad for it. Flooring a car from a dead stop is one of the worst... also its auto. So the TQ converter will be the one taking the damage... anyway to each their own. I wish we had more of a pdk transmission like Porsche. But 8 speed. That way we could really blip through gears. Atleast on the g70. G80 could be milder.

 

[Sthompsonmv7]

Also it is common but shouldn't be.. if you want to race someone dont use the shifting options. It is slower than just using sport drive mode. We can't beat the computer. Let the car do its thing.

My opinion i use the manual shift options for gear control through a turn or when slowing quickly. And yes if I am on a steep decline.
If it was a horrible thing for our cars they wouldn't give us 2 ways to-do it and offer the 10/100. But just my opinion.. thanks for reading

 

[Sthompsonmv7]

Ohhhhhh ooookkkkkk LOOOOOOOOOL

Just my opinion man. It does do more wear and tear on the car. But it is minimal. I have a pretty good friend that works as a mechanic for them right around my house. I have asked him this already.
I would say if you are experiencing transmission problems go and get a new filter/pan because its 1 in the same.. and have some fresh fluid thrown in.

 

[Sthompsonmv7]

Really? You seriously think that? The computer may prevent a shift that would outright blow the tranny, but manually shifting it down? That is going to seriously shorten the lifetime of the tranny. Replacing brake pads is a *whole* lot cheaper than a new tranny.

Well technically the transmission wears down by friction / heat.. the computer is actually saving you from blowing the engine. The engine can't handle a drop at 8k the transmission actually can. Where the fluid and transmission start to really not like it is where you bang through all the gears and then stop. Then do it all over again to a stop. That doesn't allow air to flow through our trans cooler to cool the fluid. Also the radiator. But your trans fluid is the o e that suffers. Once again. My opinion. If your going to run your car hard. Get a external cooler. Or don't do stop and go racing. Plus our cars are so heavy it is hard on a lot of parts. I mean.... do.it.but. not often

 

[Cali Gen]

Just my opinion man. It does do more wear and tear on the car. But it is minimal. I have a pretty good friend that works as a mechanic for them right around my house. I have asked him this already.
I would say if you are experiencing transmission problems go and get a new filter/pan because its 1 in the same.. and have some fresh fluid thrown in.

Don't get me wrong I agree with what you're saying and the scenarios you've provided.. but the OP described its as it being a usual thing to go from hwy speeds to stopped at a traffic light.. as you've said.. no way humans are going to downshift smoother/better than the computer the car was built with right? At least not in terms of preserving the powertrain. Agreed?

 

[amartz]

Don't get me wrong I agree with what you're saying and the scenarios you've provided.. but the OP described its as it being a usual thing to go from hwy speeds to stopped at a traffic light.. as you've said.. no way humans are going to downshift smoother/better than the computer the car was built with right? At least not in terms of preserving the powertrain. Agreed?

Sorry, but I disagree completely. If you've got a manual transmission and can feather the clutch in for a smooth downshift, fine. Auto transmissions tend slam into the lower gear. I've yet to see one that can do it smoothly. When an auto up-shifts, there is normally a little overlap between the bands, where the new one has engaged before the old band completely lets go, so that you don't get a "thunk" on the up-shift. I have yet to see an auto transmission with the valve body programmed to do a similar smooth downshift. Downshifting from 8th to 7th, sure, that's not going to put much strain on it. Downshifting from 5th to 4th, that's a different story, unless you are going so slow that it should already be in 4th already. But for engine braking? No way!

 

[Sthompsonmv7]

Sorry, but I disagree completely. If you've got a manual transmission and can feather the clutch in for a smooth downshift, fine. Auto transmissions tend slam into the lower gear. I've yet to see one that can do it smoothly. When an auto up-shifts, there is normally a little overlap between the bands, where the new one has engaged before the old band completely lets go, so that you don't get a "thunk" on the up-shift. I have yet to see an auto transmission with the valve body programmed to do a similar smooth downshift. Downshifting from 8th to 7th, sure, that's not going to put much strain on it. Downshifting from 5th to 4th, that's a different story, unless you are going so slow that it should already be in 4th already. But for engine braking? No way!

If you've been in a Porsche with the 7 speed pdk transmission you will redact your comment.

 

[MrBrady]

I took my 2014 R-Spec to the dealer b/c in automatic mode, I felt like the transmission was dragging - like it would slow down quicker than I expect, without using the brakes. It doesn't coast well. The dealer (service director, mind you) drove the car around the block with me in it and said it was completely normal. The car's computers allow it to do engine braking b/c it uses so little fuel and saves the brake pads. To me this didn't make a lot of sense and I almost laughed when he said that. But I'm not expert either.

 

[EdP]

I took my 2014 R-Spec to the dealer b/c in automatic mode, I felt like the transmission was dragging - like it would slow down quicker than I expect, without using the brakes. It doesn't coast well. The dealer (service director, mind you) drove the car around the block with me in it and said it was completely normal. The car's computers allow it to do engine braking b/c it uses so little fuel and saves the brake pads. To me this didn't make a lot of sense and I almost laughed when he said that. But I'm not expert either.

Has it always been like that or is this something new? Since none of us can drive your car we have no feel for how much it is slowing. I've had cars that seemed to coast forever, others that felt like you hit the brakes.
Perhaps you can get someone from a transmission shop to drive it or another owner of the same model to compare it with.