dot 3 or dot 5
Posting Guru
Joined: Dec 2010
Posts: 1,240
Likes: 2
From: Chino Hills
Dot 3 is now the standard, ands works great.
Dot 5 synthetic restists water accumalation, and is the best is you have the time to do it right.
Normal brake fluid is hydroscopic. Which means it absorbs atmospheric moisture which causes it to break down.
Cargo Master
Joined: Jul 2006
Posts: 3,014
Likes: 91
From: Concord, CA
Supposedly you need to change out your system if you switch to silicon fluid as the two can form a sludge when mixed together. Very few OE manufacturers use Dot 5 anyway so why would you. I don't bother at all. A better fluid would be DOT 5.1 which is still a glycol base with a higher boiling point. That also means it's affinity to attract moisture is lower.
The simple thing to do is change out the fluid every year. Not as hard as it seems. First thing is I bought a large vacuum sump/canister system from Griot's. What a time and back saver that thing has turned out to be with 8 cars. Now I just pop the top on the master cylinder and use my old turkey baster to remove the fluid from it. Then I pour new fluid in and hook up my vacuum device. Pump it up to create a vacuum, open the valve and out comes all the old fluid in that particular line. Check the master, top off, and do for another 15-20 seconds before closing the bleeder valve and onto the next. Takes me about 20 minutes to do each year at the same time as an oil change on all the older cars.
The simple thing to do is change out the fluid every year. Not as hard as it seems. First thing is I bought a large vacuum sump/canister system from Griot's. What a time and back saver that thing has turned out to be with 8 cars. Now I just pop the top on the master cylinder and use my old turkey baster to remove the fluid from it. Then I pour new fluid in and hook up my vacuum device. Pump it up to create a vacuum, open the valve and out comes all the old fluid in that particular line. Check the master, top off, and do for another 15-20 seconds before closing the bleeder valve and onto the next. Takes me about 20 minutes to do each year at the same time as an oil change on all the older cars.
Posting Guru
Joined: Jan 2002
Posts: 1,836
Likes: 3
From: Elizabethtown, PA
DOT 3 is fine. I've talked to a lot of guys who have used synthetic DOT 5 and every one has wound up changing back to 3 for one reason or another.
Annual changes are probably overkill. Back before they really expanded the service intervals on new cars, the suggested frequency was every 30,000. Very few cars actually get this done, ever, and brake problems are pretty infrequent until you get really high miles and stuff wears out. The main purposes of flushing are twofold, IMO: one, to purge any water that's been brought into the system, and two, fresh fluid makes rubber parts happier. I've got a Subaru with 155,000 on it and the hydraulic clutch system is getting tired, but I've gotten longer life from it with more frequent fluid replacements (luckily, it has it's own reservoir).
Annual changes are probably overkill. Back before they really expanded the service intervals on new cars, the suggested frequency was every 30,000. Very few cars actually get this done, ever, and brake problems are pretty infrequent until you get really high miles and stuff wears out. The main purposes of flushing are twofold, IMO: one, to purge any water that's been brought into the system, and two, fresh fluid makes rubber parts happier. I've got a Subaru with 155,000 on it and the hydraulic clutch system is getting tired, but I've gotten longer life from it with more frequent fluid replacements (luckily, it has it's own reservoir).
Thread
Thread Starter
Forum
Replies
Last Post
F-250 WARHORSE
1987 - 1996 F150 & Larger F-Series Trucks
5
Nov 12, 2013 08:35 PM
supercab78
Brakes, Steering, Suspension, Tires, & Wheels
2
May 21, 2007 06:58 PM
olthunter
1980 - 1986 Bullnose F100, F150 & Larger F-Series Trucks
3
Aug 17, 2001 10:35 PM
