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penfold
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Should that not be the other way round? 5.1 has a higher boiling point than 4, which is the main criteria for brake fluid.
Woody.v8
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Errm yes! well spotted, You passed the test
But come on, In a road based landrover or any land rover for that matter, Unless your planning on doing the pari dakar rally raid, DOT 4 is gonna do the Biz.
Brake fluid manufacturers can and often do improve on these figures and it is possible to find DOT 4 brake fluid with a higher boiling point than some DOT 5.1 fluids on the market.
migmag
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Errm yes! well spotted, You passed the test
But come on, In a road based landrover or any land rover for that matter, Unless your planning on doing the pari dakar rally raid, DOT 4 is gonna do the Biz.
Brake fluid manufacturers can and often do improve on these figures and it is possible to find DOT 4 brake fluid with a higher boiling point than some DOT 5.1 fluids on the market.
Can't believe you don't think a 4x4 would not be heavy on its brakes if nowt else they are the best towing vehicles which puts loads of strain on the brakes....
brightspark
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thats the general idea for having braked trailers--
mr migwire
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always had dot4 in my 90 towing a 1.5ton mini digger on a 1 ton plant trailer and never had a problem with stopping... buy what you can afford kim but rest assured all fluids are tested and will do the job.
It's mixing them that can cause problems. Just had to change the master cylinder on my Thwaites 2 ton dumper truck, as someone had put DOT type fluid in, but as it's a wet brakes machine (ie disks immersed in the axle oil) it uses mineral based LHM fluid. The DOT reacts and jams the seals - no seals sold separately for the Frenos Iruna Spanish cylinder - £165 for a replacement 
penfold
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It's got to be worth pulling it apart and taking the bits to a hydraulic engineers to see if they can match the seals at that price?It's mixing them that can cause problems. Just had to change the master cylinder on my Thwaites 2 ton dumper truck, as someone had put DOT type fluid in, but as it's a wet brakes machine (ie disks immersed in the axle oil) it uses mineral based LHM fluid. The DOT reacts and jams the seals - no seals sold separately for the Frenos Iruna Spanish cylinder - £165 for a replacement
It's binned now. It had jammed solid for over a year then rusted up so it would at least need honing fairly aggressively. Only way to release the foot brake was to release the fluid - I then drove it for a year on the hand brake alone
Bill Edwards
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Towing shouldn't require the vehicle brakes to do any more work, overrun brakes should take care of the entire trailer braking.
But in the real world (and rightly or wrongly) there are huge numbers of trailers out there with inadequate or totally non existent brakes which do put the braking requirements on the tow vehicle. If driven sensibly and properly this needn't require prolonged application of the brakes needing a system that can cope with high temperatures, you should put the vehicle in a low gear and let the engine do the braking - and enjoy the scenery as you pass it very, very slowly - towing is not about rushing.
People who put heavy unbraked trailers behind their vehicles and go down hills with their foot on the brake keeping the outfit at a slow speed are at high risk of boiling the fluid.
But in the real world (and rightly or wrongly) there are huge numbers of trailers out there with inadequate or totally non existent brakes which do put the braking requirements on the tow vehicle. If driven sensibly and properly this needn't require prolonged application of the brakes needing a system that can cope with high temperatures, you should put the vehicle in a low gear and let the engine do the braking - and enjoy the scenery as you pass it very, very slowly - towing is not about rushing.
People who put heavy unbraked trailers behind their vehicles and go down hills with their foot on the brake keeping the outfit at a slow speed are at high risk of boiling the fluid.
brightspark
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tjheres not a lot of breaking on modern engines as the flywheels are -nowhere near the size they used to be
pedrobedro
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DOT 4 and DOT 5.1 are compatible but DOT 5 is not. If you use the Dot 5 check your seals are compatible with it and it compresses more than mineral oil so you will have a more elastic pedal. Good quality DOT 4 can be just as good as Dot 5 or DOT 5.1. Stick with the original is always my plan and I've never had any problem with it.
Engine braking is down to compression not flywheel weight.
Engine braking is down to compression not flywheel weight.
Bill Edwards
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Flywheel weight shouldn't make any difference when going down a hill.
Basically, with some weight behind it's often a case of 2nd or 1st gear, sit back and relax. Ignore those behind, that's life!
DOT 4 is perfect for a Landrover, DOT 5 of any type is more hygroscopic to the point where you should change every 12 months or less, it's ok for a race car but no good for a road vehicle.
The trailer brakes if working should be sufficient to stop the load carried, if you rely solely on the vehicle brakes your in trouble.
Hope that helps and nice project done such rebuilds many times before and they take time patients and money.
The trailer brakes if working should be sufficient to stop the load carried, if you rely solely on the vehicle brakes your in trouble.
Hope that helps and nice project done such rebuilds many times before and they take time patients and money.
Woody.v8
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It isn't that I don,t Think, I know, I build and race cars that have their brakes on fire, And have towed some stupid weights in daft conditions with a special types HGV, So its more than just an educated guess.
