New Drums where put on I checked.
Iāve never had to replace an axle seal on my Ford truck, 50 years, 200k+ miles. Iām not sure what causes them to fail. Pretty simple gadget. Failures might be caused the physical seal design, the material they are made of, or perhaps driving style or driving a lot of extra- dusty roads.
No. In all drum systems, the shoes were hinged at the top by the wheel cylinder and the adjustment (star wheel) was at the bottom. As the shoes and drums wore down, adjusting the star wheel would keep the wheel cylinder operation in a very narrow range.
In modern disc/drum systems, the shoes hinge at the bottom and the star wheel is just under the wheel cylinder. A the shoes and drum wear, the seals in the wheel cylinder work their way out to the edges of the cylinder and can leak. Resurfacing the drum aggravates this.
I have on my old Nissan truck. One seal was clearly leaking, you could see the trail coming from the seal. Pulled both axles, both seals were pliable, had no tears and showed no wear. Replaced them, no leaks.
Interesting tidbit about drum brakes I learned recently. The rear and front shoe work together by a sort of servo mechanism that more forcefully stops the vehicle. This brake shoe arrangement increases stopping force in the forward direction, but decreases it in the reverse direction. The interesting tidbit is that on some vehicles , only applies to the rear shoes brakes, the shoes are arranged so one wheel stops more forcefully in the forward direction, and the other wheel in the reverse direction.
That was new to me, thanks. But from what I can find, the 2004 Dakota was the last year with the old-style drum brakes, adjuster at the bottom:
edit - Rockauto shows the old style shoes for the 2004, the new style shoes for 2005.
Where did you see this? Iād be interested in how itās accomplished. It would seem to create uneven rear axle braking, a very bad thing in low traction situations.
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I donāt know if anybody else knows this. but brake drums have a MAX diameter casted on them so theyāre not machined to where a wheel cylinder piston can overextend and cause leaking.
Tester
It seems like a questionable idea to me also, but apparently thatās the configuration on an early Simca 1000. To give better braking performance when in reverse and when parking. It also reduces the total rear braking force, so reduces back-end skidding. Maybe there is something about that car that makes it work, while it wouldnāt in another car.
I know from recent brake work my truckās rear drums have the size number in the same location. Itās a little hard to see, might not notice if not looking for it. I presume it is on the front drums too. .
You do realize those who machine drums/rotors know that thereās a min/max specification?
And they measure for that to determine whether or not the component can be machined?
Probably not.
Tester
Thanks for everyoneās input and information, just left over brake fluid. Axle seals are good as well as the drums.
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There is no such thing as ātiny amountā of brake fluid oozing. Iām sure there are plenty of oil, ATF, etc. leaks on your truck but that you can live with by checking level regularly and topping it off. But NOT brake fluid. Just replace the cylinder(s) and - if contaminated - shoes.
His original post only indicated new drums, later post he indicates all brake components replace. Brake fluid on backing plate likely from replacing old brake cylinders.
Or from bleeding the new brake cylinders (more likely, I think).
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