Morris Minor Owners Club

Posted: **Tue Oct 28, 2025 2:01 pm**

purchased complete Lockheed cylinder set front and back and wondering if it's best to use Dot 4 or 5 with them ?

Thank you.

Posted: **Tue Oct 28, 2025 3:18 pm**

I would always go Dot 5

Posted: **Tue Oct 28, 2025 3:47 pm**

What is already in the system? I agree that DOT5 is by far the best, but you cannot mix DOT4 and DOT5 (Silicone). As well as changing the wheel cylinders, you need to flush out any DOT4 fluid and then ideally change the master cylinder and the flexible hoses. As you are already changing the wheel cylinders, now is the ideal time complete the change.

Posted: **Tue Oct 28, 2025 4:06 pm**

It has a new lockheed master and new flexible hoses fitted, but has DOT4 In at moment.

simmitc wrote: ↑Tue Oct 28, 2025 3:47 pm What is already in the system? I agree that DOT5 is by far the best, but you cannot mix DOT4 and DOT5 (Silicone). As well as changing the wheel cylinders, you need to flush out any DOT4 fluid and then ideally change the master cylinder and the flexible hoses. As you are already changing the wheel cylinders, now is the ideal time complete the change.

Morris Minor Owners Club

Dot 4 or 5

Dot 4 or 5

Re: Dot 4 or 5

Re: Dot 4 or 5

Re: Dot 4 or 5