I'm just finishing up with a brake job on my XK120. I've replaced the shoes, turned the drums, installed new Wheel Cylinders all around. A car buddy told me to use LMA Castrol brake fluid. All I see listed is Synthetic Dot4 fluid. What am I missing on this? I've been told if I use the synthetic fluid it will cause problems. I'd appreciate any input that you members can provide me with. thanks, george

 

All brake fluid is synthetic.

Perhaps you're thinking of silicone brake fluid? It has mixed reviews/opinions.

Cheers
DD

 

Back in the 1970s/1980s I used to rebuild Jaguar Brake cylinders and people that used DOT 3 fluid would have problems with the seal swelling. The British used different seals than US manufacturers so it was important to use the correct fluid.

The US government regulated the specs for brake fluid and some did not meet regulations. Girling Green and some others were not available but CASTROL LMA (Low Moisture Affinity) did meet the specs.

That has been the 'go-to' fluid for all British cars except for Rolls Royce from the Silver Shadow onward (They required RR363).

I don't know if the modern seal kits are neoprene and the common fluids are compatible so I would recommend staying with Castrol LMA GT fluid.




https://www.ebay.com/itm/Castrol-125...53.m1438.l2649



Good luck with your research and let us know what you find.

bob

 

I think present day replacement seals must be compatible, Bob. I used the LMA for ages but all the local stores stopped carrying it so I switched to other brands 12-14 years ago. I was a bit worried but actually haven't had any problems

Cheers
DD