Hello, I just bought an M109A3 and I'm new at this. The truck has a soft pedal. It's in great shape and I believe has low mileage and hours. My buddy and I where going to bleed the brakes, but where not sure what to use in the master cyl. There is a tag inside the door with the name of the unit which did the maintenance on the truck with a phone #. So we called and spoke to a very nice mechanic. The fluid in the 109 I have is lemon yellow and I told him this. He told me that it's hydraulic oil 10 wt. I went to the hydraulic shop and they told me AW32 = 10wt. I called the mechanic again and he said that was correct. I asked why hydraulic oil instead of DOT 5. He told me that when units operate outside of the US, DOT 5 is not always available or accessible to a isolated unit and that 10 wt usually is. So now they use this. I played with some DOt 5 and the oil. They seem to mix and act compatable. I took a sample of the stuff in the master cyl and mixed it too. Didnt see any problem with this either. Anybody know about this? Thanks
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? Bleeding brakes, AW32, Hydraulic oil
- Thread starter s4mm4n16
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Clay James
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Dot 5 is the correct fluid to use and it can turn yellowish over time.
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That mechanic is feeding you a line of BS that will ruin your day for a week or more if you follow it.
If you put hydraulic oil into your master cylinder, you will very shortly need to replace all of the rubber parts in your master cylinder, air pack, and wheel cylinders. You will also have to remove every last drop, or smear of oil that is inside of the brake lines, wheel cylinders, etc..
The rubber used in brake parts is not compatible with any petroleum product. It will swell up so much that it fills all available space in the various assemblies.
DON'T PUT ANYTHING BUT A DOT APPROVED FLUID IN YOUR BRAKING SYSTEM!
-Chuck
If you put hydraulic oil into your master cylinder, you will very shortly need to replace all of the rubber parts in your master cylinder, air pack, and wheel cylinders. You will also have to remove every last drop, or smear of oil that is inside of the brake lines, wheel cylinders, etc..
The rubber used in brake parts is not compatible with any petroleum product. It will swell up so much that it fills all available space in the various assemblies.
DON'T PUT ANYTHING BUT A DOT APPROVED FLUID IN YOUR BRAKING SYSTEM!
-Chuck
Marlboro
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You can flush with de-natured alchol, flush it a few times its cheap... Then add your DOT 5
nk14zp
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GROAN!
If you haven't bled the brakes, it is possible that you can contain the damage by removing the brake line that leaves the master cylinder, and cleaning it, and rebuilding, or replacing the master cylinder.
However, if you don't get ALL of the petroleum oil out of your brake system, and I do mean ALL, your 14,000 lb truck will suffer a catastrophic brake failure where any rubber part that the oil touches will swell up huge, and cause the whole brake system to fail to operate.
So, the only way to be really certain that you have corrected this mistake is to disassemble the master cylinder, and throw away all of the rubber parts. Disassemble the air pack, and throw away all of the rubber hydraulic parts. Disassemble all wheel cylinders, and throw away all rubber parts.
Next, you need to thoroughly flush all of the brake lines with isopropyl alcohol, and scrub all of the various castings (master, airpack, wheel cylinder...) and parts with clean isopropyl alcohol, and then blow dry everything with compressed air... Then you flush, and wipe everything, with DOT5 to keep it from rusting.
Replace all of the rubber parts with new, in the usual manner done with a rebuild. Then pressure bleed everything with DOT5 in the usual manner.
The problem is, if you are inexperienced enough to even think that putting petroleum oil in a brake system is a good idea, you really are too inexperienced to be working on critical safety systems, like brakes, and inherently dangerous stuff, like jacking up trucks, and rebuilding axles... You need to get a mechanic to do this repair, or to work along side of you as you do this repair.
-Chuck
If you haven't bled the brakes, it is possible that you can contain the damage by removing the brake line that leaves the master cylinder, and cleaning it, and rebuilding, or replacing the master cylinder.
However, if you don't get ALL of the petroleum oil out of your brake system, and I do mean ALL, your 14,000 lb truck will suffer a catastrophic brake failure where any rubber part that the oil touches will swell up huge, and cause the whole brake system to fail to operate.
So, the only way to be really certain that you have corrected this mistake is to disassemble the master cylinder, and throw away all of the rubber parts. Disassemble the air pack, and throw away all of the rubber hydraulic parts. Disassemble all wheel cylinders, and throw away all rubber parts.
Next, you need to thoroughly flush all of the brake lines with isopropyl alcohol, and scrub all of the various castings (master, airpack, wheel cylinder...) and parts with clean isopropyl alcohol, and then blow dry everything with compressed air... Then you flush, and wipe everything, with DOT5 to keep it from rusting.
Replace all of the rubber parts with new, in the usual manner done with a rebuild. Then pressure bleed everything with DOT5 in the usual manner.
The problem is, if you are inexperienced enough to even think that putting petroleum oil in a brake system is a good idea, you really are too inexperienced to be working on critical safety systems, like brakes, and inherently dangerous stuff, like jacking up trucks, and rebuilding axles... You need to get a mechanic to do this repair, or to work along side of you as you do this repair.
-Chuck
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I REALLY hate to say this, but READING the TMs WOULD have saved ALL this MESS, HASSEL, and EXPENSE.
YES, 10wt, hyd. can be used in the brake system, BUT only in a FIELD EMERGENCY when the proper fluid is not available to get the truck going, but NOT as a EVERYDAY use.
I have a older (cold war) FM that tells what can be used to replace what in a combat need situation, right now it is MIA and has been for a while, I'll launch a search mission at the time the need appears a lot higher on my to do list then it is now..
YES, 10wt, hyd. can be used in the brake system, BUT only in a FIELD EMERGENCY when the proper fluid is not available to get the truck going, but NOT as a EVERYDAY use.
I have a older (cold war) FM that tells what can be used to replace what in a combat need situation, right now it is MIA and has been for a while, I'll launch a search mission at the time the need appears a lot higher on my to do list then it is now..
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Heavysteven
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Brake system in a deuce is DOT 5 and the color is purple when new. It fades to golden yellow with time.
schwenk industries
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Look in TM 9-2320-361-20 (for the tear down if needed)
sections (SERVICE BRAKE AND HYDRAULIC SYSTEMS MAINTENANCE) Table of contents page 592 (of pdf)
8-24
8-26
8-30
possibly 8-18 but probably not. in case you don't have it Here you go
i hope it works for ya good luck.(i shortened the file to just the brake section so it would not take for ever)
sections (SERVICE BRAKE AND HYDRAULIC SYSTEMS MAINTENANCE) Table of contents page 592 (of pdf)
8-24
8-26
8-30
possibly 8-18 but probably not. in case you don't have it Here you go
i hope it works for ya good luck.(i shortened the file to just the brake section so it would not take for ever)
M35 brakes, I definitely screwed up!!!
Thanks all for your responses. As I explained in my original post, I am new at the M35 program, but have had experience in the past with Willys jeeps and other vehicles. Also, I was aware that the DOT 5 is the recomended fluid. What changed my mind was the Tag in the truck that said that the service was done at Fort Riley KS and there was a phone #. I call this number and spoke to a very nice (older sounding) gentelman who I was refered to when calling. I told him what I had and he was the one who told me that it sounded to him like 10 wt. oil and sent me a email saying that. Everyone else around here that I talked to never heard of yellow brake fluid. I thought that it would be best to match the fluid with LIKE fluid, so I did. I realize that this is going to cost me time a money to get it right again, but maybe it is for the best and as a result, I found you guys! Wht I don't get, is that this guy is a head mechanic (I think) for the US Army and services vehicles. Thats Scarry! I almost feel like calling him back and telling him what happened and asking him to send me the rebuild kits for the entire truck brake system. What do you guys think??
Thanks for your responses and I will be here again for the professional advice when I need it.
Many Thanks,
Bob
Thanks all for your responses. As I explained in my original post, I am new at the M35 program, but have had experience in the past with Willys jeeps and other vehicles. Also, I was aware that the DOT 5 is the recomended fluid. What changed my mind was the Tag in the truck that said that the service was done at Fort Riley KS and there was a phone #. I call this number and spoke to a very nice (older sounding) gentelman who I was refered to when calling. I told him what I had and he was the one who told me that it sounded to him like 10 wt. oil and sent me a email saying that. Everyone else around here that I talked to never heard of yellow brake fluid. I thought that it would be best to match the fluid with LIKE fluid, so I did. I realize that this is going to cost me time a money to get it right again, but maybe it is for the best and as a result, I found you guys! Wht I don't get, is that this guy is a head mechanic (I think) for the US Army and services vehicles. Thats Scarry! I almost feel like calling him back and telling him what happened and asking him to send me the rebuild kits for the entire truck brake system. What do you guys think??
Thanks for your responses and I will be here again for the professional advice when I need it.
Many Thanks,
Bob
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I'd atleast call him and let him know.. In a nice way of course.. Then see what happens from there. Cant hurt any, and who knows what he might be able to help you out with.
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Hi Bob,
Heads of facilities are rarely available by phone without a lot of work, or insider knowledge. The guy you got is most likely some kid (regardless of his age) that was running the phones. I would bet that he would really shine at getting a wrecker out to your unit, or scheduling a PMCS for the trucks in your motor pool. He probably has never touched a wrench, and if he did, was found to be too much of a menace to continue wrenching. You can find guys just like him behind the counter at any NAPA, CarQuest, PepBoys... store.
The TM-9's are excellent books, and tell you just about everything you need to know to do a good job at maintaining and operating these trucks. The biggest problem with the TM-9 manuals is they almost never tell you why you are doing what you are doing. I think that is a big mistake, because it perpetuates ignorance. I would rather that the mechanics knew why they were never to let oil or grease into the brake system, than to just tell them use such-and-such drycleaning fluid to clean the system. It is hard to keep your eye on the prize when you don't know what the prize is.
[You might want to check out your local library and pick out a few books on automotive maintenance as "bedtime readers"... there are some out there that are heavy on the why when they discuss the how. Any time spent reading the TM-9's for your truck is time well spent. Usually every TM-9 you could want is available in the resources section of this website, but that section is currently off line because it has been hacked by spammers. In the mean time, JATONKA has generously hosted all of the deuce TM-9's on his website... which is easily found by google. Have a visit, and buy some stuff, you won't be disappointed.]
The worse looking mess I have ever seen in a brake system was on a forklift where someone put ATF in the brake reservoir. Presumably it worked for quite a while, but ultimately, the brake pedal froze hard. You couldn't move it a fraction of an inch. The master cylinder was stuffed full of the swollen up rubber piston cups... as were all of the wheel cylinders. The system had ATF throughout, so clearly the person doing this thought it was the right fluid, or thought the ATF would do something wonderful for the brakes.... I don't know which.
In a real emergency, I would use (in order of desirability) brake fluid, antifreeze, water, motor oil, hydraulic oil, diesel fuel, just about anything liquid... In a real emergency, machines are disposable.
-Chuck
Heads of facilities are rarely available by phone without a lot of work, or insider knowledge. The guy you got is most likely some kid (regardless of his age) that was running the phones. I would bet that he would really shine at getting a wrecker out to your unit, or scheduling a PMCS for the trucks in your motor pool. He probably has never touched a wrench, and if he did, was found to be too much of a menace to continue wrenching. You can find guys just like him behind the counter at any NAPA, CarQuest, PepBoys... store.
The TM-9's are excellent books, and tell you just about everything you need to know to do a good job at maintaining and operating these trucks. The biggest problem with the TM-9 manuals is they almost never tell you why you are doing what you are doing. I think that is a big mistake, because it perpetuates ignorance. I would rather that the mechanics knew why they were never to let oil or grease into the brake system, than to just tell them use such-and-such drycleaning fluid to clean the system. It is hard to keep your eye on the prize when you don't know what the prize is.
[You might want to check out your local library and pick out a few books on automotive maintenance as "bedtime readers"... there are some out there that are heavy on the why when they discuss the how. Any time spent reading the TM-9's for your truck is time well spent. Usually every TM-9 you could want is available in the resources section of this website, but that section is currently off line because it has been hacked by spammers. In the mean time, JATONKA has generously hosted all of the deuce TM-9's on his website... which is easily found by google. Have a visit, and buy some stuff, you won't be disappointed.]
The worse looking mess I have ever seen in a brake system was on a forklift where someone put ATF in the brake reservoir. Presumably it worked for quite a while, but ultimately, the brake pedal froze hard. You couldn't move it a fraction of an inch. The master cylinder was stuffed full of the swollen up rubber piston cups... as were all of the wheel cylinders. The system had ATF throughout, so clearly the person doing this thought it was the right fluid, or thought the ATF would do something wonderful for the brakes.... I don't know which.
In a real emergency, I would use (in order of desirability) brake fluid, antifreeze, water, motor oil, hydraulic oil, diesel fuel, just about anything liquid... In a real emergency, machines are disposable.
-Chuck
Clay James
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They don't always do stuff right. When I got my truck only the final filter was installed correctly. The primary was at the bottom of the canister with the spring and cup on top and the secondary was missing the cup so they both weren't filtering.
Thanks again for the replies. I thought I saw a post that said the name or site where you could buy the DOT 5 fluid for $30.00 or $35.00/gal. Anybody know? Also, who is a good source of parts for the M35s? Brake system parts for now and I am sure others in the future.
Bob
Bob
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Good luck, the cheapest I have found lately was $56.00 per gallon shipped to Texas.