Correct Brake Booster or not?

[imperigal]

Of course I waited until after I had removed the factory booster to open the box with the remanufactured booster. Mounts look the same, but is more compact. Slightly larger diameter, but doesn't stick out as far. Everything should bolt together fine, but is this the right one?

If it is not the correct one, which one should I be asking for? I requested one for a car with front disc brakes and double checked the order and part number. (AutoZone B1447) see pic for Chrysler part number.

 

[jct]

autozone is a crap shoot, when i tried to replace my booster with one of theirs they gave me a one for a one year only e-body (i think it was for a 1970 440) i returned it, and went to napa and got the correct one

 

[FURYGT]

Could you clarify what car the booster if for and if you are doing a conversion, what parts you are using for the conversion.

 

[imperigal]

This is for a 73 Chrysler T&C with a 440, disc brakes in front and AC. Maybe the cruise has something to do with needing the larger vacuum reservoir?

 

[jct]

heh quick googling shows its for a 1970 E-body. 340 340+6 383 440 440+6 Cuda and Challenger

 

[imperigal]

In the FSM, the drawing of the booster that looks most like what WAS on my car is for a 318 and 340. In the diagrams for the 440 C bodies shows a booster that looks like the new one I just got. Maybe mine was replaced with an incorrect one along the way?

 

[CBODY67]

The "thicker" booster probably is a dual-diaphragm booster, which most power disc brake cars used and needed, but I don't recall that being on our '72 Chrysler Newport with factory power disc brakes on the front. Might be that the wagons got the dual-diaphragm booster and the sedans didn't, in '72-'73? Due to the weight of the vehicle and possible intended uses (including cargo/people hauling/trailer towing RV uses), rather than just driving down the street?

For general principles, I'd recommend seeking a booster like the one removed. On the other hand, the lines would probably NOT just fall into place with the thinner booster, although the bolt-up to the firewall and master cylinder would be the same. Thinner booster would move the master cylinder rearward, making some additional bending of the existing lines necessary to hook up. Aside from the other differences, you can tell that to the AZ people. "Won't fit".

FSM illustrations are not always "absolute". By the time they are printed and distributed, some "changes in equipment" could have occurred on the assembly line items which went onto the cars. What's in the parts books should over-ride the FSM, in a few cases.

Best to match what's on the vehicle, if possible. Take your "wrong parts" case to NAPA or similar and see if THEY don't make a better effort to get you the "right parts" and be "your hero" for doing that. They should have an accurate picture of the power boosters they have available.

CBODY67

 

[imperigal]

The "thicker" booster probably is a dual-diaphragm booster, which most power disc brake cars used and needed, but I don't recall that being on our '72 Chrysler Newport with factory power disc brakes on the front. Might be that the wagons got the dual-diaphragm booster and the sedans didn't, in '72-'73? Due to the weight of the vehicle and possible intended uses (including cargo/people hauling/trailer towing RV uses), rather than just driving down the street?

For general principles, I'd recommend seeking a booster like the one removed. On the other hand, the lines would probably NOT just fall into place with the thinner booster, although the bolt-up to the firewall and master cylinder would be the same. Thinner booster would move the master cylinder rearward, making some additional bending of the existing lines necessary to hook up. Aside from the other differences, you can tell that to the AZ people. "Won't fit".

CBODY67

There's a small exception noted in the FSM - it point to the booster and indicates 'P,D,C Suburban and Y Models - Large Tandem Diaphragm'.

I've searched every auto parts store online and can't find one anywhere that is a dual/tandem diaphragm, only single. Look for someone to rebuild the original? Has anyone here purchased this wagon-specific booster? If yes, from where?

 

[imperigal]

Found it - had to look up as a 1973 Imperial. Tandem diaphragm, part 80085. Can't find the part anywhere, but found a rebuild service for $165. Guess that might be my only option unless anyone has a source!

 

[commando1]

Guess that might be my only option unless anyone has a source!

There's literally only two mass market companies left that remanufacture older Mopar boosters and they both have discontinued the dual diaphragm boosters.
Your only choice now are the mom n pop privateers that rebuild your core.

 

[Ross Wooldridge]

The new booster is correct for 73 with 440 and discs. The old booster is not.

 

[Davea Lux]

There's a small exception noted in the FSM - it point to the booster and indicates 'P,D,C Suburban and Y Models - Large Tandem Diaphragm'.

I've searched every auto parts store online and can't find one anywhere that is a dual/tandem diaphragm, only single. Look for someone to rebuild the original? Has anyone here purchased this wagon-specific booster? If yes, from where?

The tandem booster was widely used on Mopars with disc brakes up until the end of the '71 model year. In 1972 that booster was still on some specialty applications such as the heavy trailer tow package. It could also still be a "special order" option on some police cruisers. That is why the manual still shows the reference to the older style booster. I suspect that your vehicle probably had a trailer package which is why this booster was installed. If that is the case, the option code is probably on the build sheet and the build tag. If your desire is to keep the car original and to factory specs, verify the trailer package and rebuild your existing booster ($160 is a cheap price for that service). Otherwise the booster you purchased will work for your application though you may need to modify the vacuum hose setup.

Dave

 

[saforwardlook]

In 1971, Chrysler went to the single diaphram brake booster on the regular models rather than dual diaphragm on all models, except for Town & Countrys, Imperials and some special applications. If you have ever tried to stop an Imperial or a T & C without vacuum assist, you will be in for a surprise. Pressing with all my might in such situations would not stop one of those bigger models even at low speed. So if you hear hissing or feel the dual diaphragm models are losing braking assist, take care of it sooner rather than later.

 

[Carmine]

I know how much Imperigal can leg press, so I'm less concerned.

But obviously it should be fixed.

 

[imperigal]

So if I can muster up some patience, I could get the original one rebuilt. (Figure 10-14 day turnaround). But if I want to get this finished TODAY I would be able to use this one, knowing that if I'm towing something heavy, I may have difficulty stopping without standing on the brake pedal. Right?

@Davea_Lux - I try to keep the cars as original as possible, but if it's something that can always be returned to original in the future, I sometimes take that route. If I decide to go with the new one, I'll keep the tandem diaphragm to be rebuilt in the future.

 

[CBODY67]

Seems like there were TWO trailer tow option packages? One was for lighter trailers. The other one is one digit from the police package, as I recall, and would be for the "full-rated trailer weight", which would certainly need the dual-diaphragm booster at "full-rated load" or GCVW.

Might check regionally for OTR truck booster rebuilders, or similar. Or possibly somebody in the Mopar Restoration Parts side of things, for possible rebuilders.

CBODY67

 

[CBODY67]

So, you'll have to pay the core charge to keep your original booster for later.

The whole deal is about "surface area of the diaphragm" relating to the amount of boost supplied by the booster. More area, more boost.

CBODY67

 

[Carmine]

If you are willing to eat the core cost, you could keep it and swap it later. I'm sure the day will come when you or someone you know will need a lightly used rebuild.

 

[imperigal]

If you are willing to eat the core cost, you could keep it and swap it later. I'm sure the day will come when you or someone you know will need a lightly used rebuild.

The core was a whopping $5.01, so I don't mind hanging on to it :-D

 

[Carmine]

The core was a whopping $5.01, so I don't mind hanging on to it :-D

OMG that seems wrong. Now I feel like you should return it... like stealing a library book.