4 ms·

Wet. Dry have issues due to heat management and failing seals that end up slathering the clutch in lubricants. It boggles my mind that an engineer would choose

Wet. Dry have issues due to heat management and failing seals that end up slathering the clutch in lubricants. It boggles my mind that an engineer would choose dry. I think the idea was to reduce costs. In Ford's case it resulted in a fairly nasty class action law suit.

HPsquared 3y ago
Wet clutch has the problem of friction material building up in the fluid, which can cause wear and deteriorate the other components. Dry clutch is more modular, the clutch is more self-contained and seems like it would be better for long-term serviceability: if the clutch wears out, you can just replace that part.
- rozap 3y ago
  Hm thanks for reminding me that I need to change the fluid in my DSG. It's annoying that the VW manual suggests comically long service intervals for this stuff to make it look like the running costs are lower than they are. I want to just keep the car until it has 300k+ miles. But it's all about shifting those units initially.
- kube-system 3y ago
  I've always wondered if it would be able to build a car transmission with a clutch similar to a motorcycle. Those are very easy to replace.
- bri3d 3y ago
  Concentric-shaft wet DCTs aren't bad - for example, replacing the clutch pack on a VW DQ250 is very similar to replacing the torque converter on an automatic. You have to drain it but it's not particularly involved. There's basically a cover on the bell housing behind the flywheel, drain the fluid, remove the snap ring, and you're looking at the clutch pack. Lift it off and lift a new one back on. Rebuilding the clutch packs themselves is a tedious and obnoxious process, because they're a giant stack of friction material that needs to be shimmed into tolerance, but you often just buy the clutch pack as a whole assembly. I'd massively prefer a wet clutch even for long term serviceability - a few hundred dollars or less every year or two for fresh fluid and you've got a long service life before an expensive removal.
- IgorPartola 3y ago
  Wet clutches are standard in motorcycles. Lower power of course but they work very well across the entire segment.
  - fragmede 3y ago
    except for Ducati, famously
    - queuebert 3y ago
      But aren't they meant to be rebuilt every 10k miles or so?
      - IgorPartola 3y ago
        Don’t know about Ducati but on other bikes a clutch job is a stupidly simple process.
- datavirtue 3y ago
  In my experience wet clutches in automatics far outlasted any dry clutch that I was aware of. Toyotas last a long time but your bog standard iffy Ford AOD clutches would easily last beyond 200k abused. There are many clutch rings packed together and engagement is precise. Fluid changes are fairly easy...or can be. Ford has recently removed the dipsticks on their amazing 6speed truck transmission making it very difficult to change.

HPsquared 3y ago

Wet clutch has the problem of friction material building up in the fluid, which can cause wear and deteriorate the other components. Dry clutch is more modular, the clutch is more self-contained and seems like it would be better for long-term serviceability: if the clutch wears out, you can just replace that part.

rozap 3y ago
Hm thanks for reminding me that I need to change the fluid in my DSG. It's annoying that the VW manual suggests comically long service intervals for this stuff to make it look like the running costs are lower than they are. I want to just keep the car until it has 300k+ miles. But it's all about shifting those units initially.
kube-system 3y ago
I've always wondered if it would be able to build a car transmission with a clutch similar to a motorcycle. Those are very easy to replace.
bri3d 3y ago
Concentric-shaft wet DCTs aren't bad - for example, replacing the clutch pack on a VW DQ250 is very similar to replacing the torque converter on an automatic. You have to drain it but it's not particularly involved. There's basically a cover on the bell housing behind the flywheel, drain the fluid, remove the snap ring, and you're looking at the clutch pack. Lift it off and lift a new one back on. Rebuilding the clutch packs themselves is a tedious and obnoxious process, because they're a giant stack of friction material that needs to be shimmed into tolerance, but you often just buy the clutch pack as a whole assembly. I'd massively prefer a wet clutch even for long term serviceability - a few hundred dollars or less every year or two for fresh fluid and you've got a long service life before an expensive removal.
IgorPartola 3y ago
Wet clutches are standard in motorcycles. Lower power of course but they work very well across the entire segment.
- fragmede 3y ago
  except for Ducati, famously
  - queuebert 3y ago
    But aren't they meant to be rebuilt every 10k miles or so?
    - IgorPartola 3y ago
      Don’t know about Ducati but on other bikes a clutch job is a stupidly simple process.
datavirtue 3y ago
In my experience wet clutches in automatics far outlasted any dry clutch that I was aware of. Toyotas last a long time but your bog standard iffy Ford AOD clutches would easily last beyond 200k abused. There are many clutch rings packed together and engagement is precise. Fluid changes are fairly easy...or can be. Ford has recently removed the dipsticks on their amazing 6speed truck transmission making it very difficult to change.