ABS unit use DOT4 instead of DOT3. (1 Viewer)

[fredj]

Hi,
If use dot4 are there any harmful effects for ABS unit?

 

[bloc]

Hi,
If use dot4 are there any harmful effects for ABS unit?

It won't hurt it, but DOT4 absorbs moisture faster than DOT3, so it will need to be replaced sooner

 

[fredj]

It won't hurt it, but DOT4 absorbs moisture faster than DOT3, so it will need to be replaced sooner

Thank you for your help

 

[TeCKis300]

Hi,
If use dot4 are there any harmful effects for ABS unit?

No harmful effects as DOT 3 and DOT 4 are both glycol-based and compatible.

Question would be why bother with DOT 4?

It is more hygroscopic which will increase the maintenance interval. Performance won't necessarily go up with the higher boiling point if you're using stock pads. Stock pads will fade well before DOT 3 fluid boils. I find that even with performance aftermarket pads, I can reach the maximum operating temp (MOT) of the pad before brake fluid boiling is a concern. So long as the fluid is in good maintenance.

For a street car, it may not be worth bothering with a high performance DOT 4. In fact for my 911 Turbo, I downgraded the fluid and pads to more street oriented stuff as I use it as a street car first. There's no autobahn and I'm not tearing down mountains on the weekend. When I visit the track, it gets fresh DOT 4 and track oriented pads.

I just run easy to acquire Valvoline Synthetic DOT 3 & 4 on all my cars which has a solid 480F boiling point and low-moisture formula.

My 200-series has seen more canyon carving than my sports car LOL, and Valvoline Synthetic holds up. Hawk LTS pads, not so much (but that's my fault for driving them well beyond what sane people might do). They are excellent pads if you want a real upgrade.

 

[fredj]

No harmful effects as DOT 3 and DOT 4 are both glycol-based and compatible.

Question would be why bother with DOT 4?

It is more hygroscopic which will increase the maintenance interval. Performance won't necessarily go up with the higher boiling point if you're using stock pads. Stock pads will fade well before DOT 3 fluid boils. I find that even with performance aftermarket pads, I can reach the maximum operating temp (MOT) of the pad before brake fluid boiling is a concern. So long as the fluid is in good maintenance.

For a street car, it may not be worth bothering with a high performance DOT 4. In fact for my 911 Turbo, I downgraded the fluid and pads to more street oriented stuff as I use it as a street car first. There's no autobahn and I'm not tearing down mountains on the weekend. When I visit the track, it gets fresh DOT 4 and track oriented pads.

I just run easy to acquire Valvoline Synthetic DOT 3 & 4 on all my cars which has a solid 480F boiling point and low-moisture formula.

My 200-series has seen more canyon carving than my sports car LOL, and Valvoline Synthetic holds up. Hawk LTS pads, not so much (but that's my fault for driving them well beyond what sane people might do). They are excellent pads if you want a real upgrade.

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Thank you for your detailed reply, I really appreciate it.

I would like to use DOT4 just because it is available in high quality, unlike the DOT3, which comes in low quality. When I used the low quality Dot 3, I noticed that the ABS pump operating cycles became very short.

after a short time of operation, maybe half an hour, the ABS unit became very hot that I cannot touch. And sometimes ABS light ON with beeping.

I know that the problem could be bigger than just changing the type of fluid, I will try Dot 4, maybe something different will happen.