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Mechanic: "Install Brake Booster on your 79 VW Rabbit"

So I took my '79 VW Rabbit to get the tires replaced and the Mechanic HIGHLY recommended that I install a brake booster.

He quoted me $200 plus $60 in labor.



The manual brakes work decently; so is this really a safety issue?

Is it really just a one hour install?

Since I don’t have ABS, I have to pump the brakes when i stop suddenly. Will the brake booster make the tapping easier? Will it make locking my brakes easier?

P.S. It’s a Diesel. I hear that changes something with how the vacuum on the booster works?

Replace it! Don’t mess around when it comes to yours and others safety.

If your brake booster is defective, you need to know if it’s the booster or the check valve. The check valve is replacable.

Generally, the advantage with power brakes is that because you’re not having to stomp down on the brake pedal with all your might, you have better control on how much braking force you’re applying, which makes it easier to brake hard but not so hard as to lock up the wheels. I don’t think driving around in a car with manual brakes is the most dangerous thing in the world, but they would be nice to have. If this guy knows his VW’s, I’d say the price is right.

The issue with diesels is that they don’t generate any vacuum because they have no throttle, but your car probably has an auxillary vacuum pump that runs the heater blend doors and should have no problem running a brake booster.

EDIT: I assumed this is a car that didn’t come with power brakes in the first place. Is that right?

I don’t think this car had a booster to begin with.

I don’t think this car had a booster to begin with.

I went searching and while I did not find a booster for a gas Rabbit older than '81, I did find one for diesels.

That’s right. No Power Brake Booster to Begin with.

Mechanic says we should install one. I’ve read that, because it’s diesel, I won’t just need a brake booster, but an electric vacuum to suck air as well.

Is this a minor thing that he didn’t mention because it costs $25. Or is installing power brake boosters on manual brakes the sort of thing that he comes back to me with “well, you see… in order to install the boosters we had to install an electric pump to feed the vacuum, and in order to that…etc.”?

Forgive my na?ve paranoia. Once bitten, twice shy.

Okay. So electric pump doesn’t apply to my Rabbit?

How long have you had this car? Does it have a brake booster now, and if so, does the booster work?

If it doesn’t have a booster, and never had a booster, then you don’t need a booster now.

You say you took your car to have tires replaced. Where did you take it? Some tire chain stores just LOVE to find things for which they can charge you more money. Is this, perhaps, the case here?

Diesel engines don’t create vacuum the way gasoline engines do, so if you want to install a vacuum brake booster you’d need an electric vacuum pump. I doubt $25 would do it. This would probably end up costing LOTS of money, and there would be no benefit. It might even be detrimental to the car.

I think you should forget what this “mechanic” suggested, and continue to drive your diesel Rabbit the way the VW engineers designed it. They knew what they were doing then, and there’s no reason to question them now.

I can’t think of any reason why you’d need a vacuum brake booster on this car.

He’s only said it didn’t come with one three times…

But I think this really gets to the core of the issue. If this was just some guy who works at the tire place, forget about it. But, if the guy is somebody with experiance with VW diesels who seems to understand the full ramifications of the project, that seems like a pretty good price to add power brakes. These were probably one of the least safe cars ever made (they did far worse than the old beetles in crash tests) and you need all the help you can get!

Actually, I dunno-- I know the newer ones used vacuum blend doors and had auxillary vacuum pumps, but these might have used cables for the vents and so perhaps you would need to add a vacuum pump.

Okay, Updates.
Apparently the car had a power booster an owner or so back.
The mechanic is not just a tire shlub but a full-fledged VW mechanic.
So, that said, i’ll take this forum’s advice that this a fair price.
And since, as the old owner just disclosed, the brakes weren’t always “manual”, i’m going to do what the VW designers intended and ride the car with power brakes.

Thanks so much for the feedback.
On a side note…worse in safety tests than the beetle???

Do you really want to go there?

Brake booster or lack of one is not going to solve a problem of tapping the brakes to develop a pedal.
A VW diesel has a vacuum pump. It’s mechanically operated and is located where the distributor would be on a gasoline car.

If you have a pedal problem then that’s either failing hydraulics (master cylinder, wheel cylinder, etc., OR the rear brakes are badly worn and need replacement or adjustment. Check the rear brakes first.

As to any safety issues about crashes, that’s a non-issue. Do a net search for the NHTSA data, compare the 79 Rabbit with other 1979 vehicles, and you’ll find the Rabbit is no worse than many other similar types of cars for that year and in fact, often exceeds them.

Yes, actually the thing about the Beetle outperforming the Rabbit has more to do with the fact that the Beetle was a bit more robust than an average compact car of the day, especially in rollovers and rear-end collisions. I think the main reason why the Beetles got a reputation as a deathtrap was just because they were the first compact cars that sold in great numbers in the US.

If you feel that the car stops adequately and fast in a panic situation, then don’t bother with the booster and required vacuum pump.

According to my information too, VW diesels did not have boosters before 1981 and I have not heard of complaints about the lack of a booster.

You might want to post your question on the brake forum at www.vwvortex.com. Car Talk is good but Vortex.com is better for VWs.

Here is a little more about this.

According to my sources, there is a different master cylinder too if you change to power brakes. I would be skeptical about your mechanic charging you only $260 total for a booster, master cylinder and an electric vacuum pump for that amount. Possibly he will used salvaged parts for the master cylinder and booster and who can say that the electric vacuum pump is new? He will need to install a hose for the pump, wire for the vacuum motor and your brake lines will need to be revised a little to accomodate the different position for the master cylinder due to the thickness of the booster. The price borders on unreal if new parts are used unless the Chinese are making this stuff now.