1967-69 Camaro Suspension, Brakes and Wheels

1. Mono Leaf and Multi Leaf Spring Usage
2. Front Suspension A-Arms
3. Brake Systems
4. Brake Boosters and Master Cylinders
5. Wheels

Mono-leaf and Multi-leaf Spring Usage

All 6-cylinder cars for all 3 years came with monoleaf springs.

All 1967 models used monoleaf design rear springs.

For 1968, only models with the 12-bolt rear end received multi-leaf springs. This included all SS models, the Z28, and the L30/M20 327/275hp 4-speed. All other 1968 models used monoleaf springs.

In 1969, all models with 12-bolt axles received multi-leaf springs and all models with 350ci engines (10- or 12-bolt) received multi-leaf springs. Vehicles with 307 and 327 engines received mono-leaf springs.

The spring rates varied depending on the model, vehicle weight, and spring options (F41 and G31). The spring part numbers and weight ranges are shown in the parts manuals and the ride heights are shown in the Assembly Instruction Manual. Note that not all spring part numbers were sold as service parts and not all are not reproduced.

Upper A-Arms
The upper a-arms used for all 67-68 Camaros and 69 Camaros with drum brakes and JL8 four-wheel disc brakes were the same design. The 69 J52 disc brake cars used the same basic part, but there were two holes added to the trailing side of the a-arm for mounting a support for the brake hose.

Lower A-Arms
The lower a-arms used for the 1st-gen Camaros had small but noticeable differences for all three years. This was primarily due to changes in the location of the rubber bump stop which was used to cushion any contact with the frame upon full compression of the suspension. It is unknown why the location of the rubber bump stop changed each year.

In 67, the rubber bump stop was mounted on a bracket which was welded to the frame, thus there is no rubber piece mounted on the lower a-arm and no holes drilled in the a-arm to do so. For 68, a newly designed larger rubber bump stop was mounted (through two drilled holes) on the trailing side of the a-arm. The mounting bracket for the rubber bump stop (which had been in-line with the centerline of the wheel in 67) was removed and a newly designed metal contact pad for the rubber bump stop was mounted on the trailing side of the coil spring pocket on the frame. For 69, the same rubber bump stop was moved to the leading edge of the lower a-arm and the corresponding metal contact pad on the frame followed suit to the leading side of the coil spring pocket. All service replacement a-arms included mounting holes for both the 68 and 69 positioning of the rubber bump stop. Obviously, these holes are not relevant for the 67 application since the rubber piece is on the frame.

The 67 and 68 lower a-arms use welded-in nuts for the lower shock mount. For 69 and for all service replacement a-arms, the shock mounting nuts were attached by a J-clip, which simplified the nut installation and also allowed for easy replacement.

The Assembly Instruction Manuals for all three years show different part numbers for the lower a-arm assembly for drum brakes and the lower a-arm assembly for disc brakes. Despite analysis of the parts, the difference is unknown; it may involve another component of the a-arm assembly.

1967-69 Camaro Lower A-Arm Comparison

1967

Manual drum brakes on all four wheels were standard for all models except Z28. The power assist option was RPO J50 and the front disc brake option was RPO J52. Power assist was not required with the front disc brakes. Power front disc brakes required both J50 and J52 options. While SS neither included nor required front disc brakes, the J50/J52 combination was a mandatory option for Z28. The disc calipers were a 4-piston design used only in 67 and 68.

1967 included two one-year-only brake options. The RPO J65 metallic pad drum brake option added metallic brake shoes on all 4 drums. J65 was supposedly only available on 67 SS's but it has been observed on a few non-SS cars.

The RPO J56 heavy duty disc brake option was only available on 67 Z28's and was in addition to the required J50 and J52 options. It consisted of metallic disc brake pads with heat insulators on the caliper pistons and metallic rear drum linings. Both RPO J65 and J56 used the same metallic rear drum linings (and thus used the same metallic brake rear axle assemblies).

1968

Manual drum brakes on all four wheels remained standard for all models except Z28. RPO J50 power assist remained a separate option for drum brakes, but RPO J52 front disc brakes now included RPO J50, and thus all 1968 disc brakes were also power disc brakes. While SS neither included nor required J52 front disc brakes, RPO J52 was a mandatory option for Z28. This was the last year for the 4-piston disc brake calipers used only in 67 and 68.

1969

Manual drum brakes on all four wheels remained standard for base models, and RPO J50 power assist remained a separate option for drum brakes. RPO J52 power front disc brakes were now included in all SS models, and this RPO remained a mandatory option for Z28. The disc brakes in 1969 were redesigned to a single-piston caliper that replaced the more complicated and costly 4-piston design.

 

RPO JL8 4-Wheel Disc Brakes

To support the Z28 in Trans Am racing, a four-wheel disc brake system was released as over-the-counter (OTC) heavy-duty service parts in March of 1968. The system was adapted from the Corvette J56 heavy-duty brake package and included larger front and rear rotors (11 3/4" vs 11" for the production J52 rotor). Though included in the 1968 assembly manual and in the POP option field information, JL8 was not a 1968 production option. The inclusion in the 1968 documentation apparently was either in preparation for a proposed option release that never occurred, or as part of a subterfuge for convincing racing authorities that the 4WD brakes were a factory option and thus qualified for Trans Am racing use.

A modified version of the OTC system was released in 1969 for production as RPO JL8, 4-Wheel Power Disc Brakes. The option was only produced during a limited timeframe, from Feb 69 to May 69, and production was only 206 units. The JL8 option was available on any Camaro model; the cost was $500.30 for SS or Z28 models and $623.50 for non-SS non-Z28 models. Most JL8's were installed on Z28's, though some non-Z28 non-SS Camaros have been verified as receiving JL8!

Many of the disc-brake rear axles that survive are the HD service units, rather than JL8. There are easily identifiable physical differences between the JL8 and the service axles. See Wayne Guinn's book, Camaro Untold Secrets 1967-1969, for details on these differences and see the JL8 article on his website for more information on the option.

Note: Disc brakes required special wheels with a different centerline-to-attach-plane offset. See the wheels information for the relationship between brakes and wheels.

1967-69 Camaros used Delco Moraine brake boosters. The application code for the booster is stamped on a tab on the top right of the booster (see picture below) and the Julian date is stamped on the other side of the tab. In 1968, both the drum and disk brake boosters changed to new part numbers during the model year and both codes are listed below.

1967-69 Camaro Brake Boosters 1967 1968 1969 ---- ---- ---- Drum 0749 0749 3972 Brakes 1109* 9079 Disc 8515 8515 9204 Brakes 9078 *J65 metallic brakes

Master Cylinders
1967-69 Camaros used Delco Moraine master cylinders. The casting number is on the the side of the master cylinder. All 67-69 drum brake cars used the 5452310 casting except 1967 J65 cars used the 5461862 casting. 1967 and 1968 disc brake cars used the 5460346 master cylinder. Early 1969 disc brake cars also used the 5460346 master cylinder (for about a month or so of production) with later 69 cars using the 5468309 casting.

The application code for the master cylinder was stamped on a small pad on the front of the casting, as shown in the sketch below. Note that the tag in the sketch had the broadcast code on it.

1969 J52 disc brakes and JL8 four wheel disc brakes both used the US-stamped master cylinder. The only difference was the J52 master cylinder had a check valve in the outlet for the rear drum brakes, whereas the JL8 master cylinder did not have any check valves.

                                    Bore 
               1967   1968   1969   Size 
               ----   ----   ----   ----
 Manual drums   BS*    BS     BS     1"
 Power drums    BS     BS     BS     1"
 Manual J65     AU     -      -     7/8"
 Power J65      ?      -      -      1"

 Manual discs   AD     -      -      1"
 Power discs    WT     WT     US   1 1/8"

 * unverified CT code has also been observed

A summary of the wheel types, applications, and their relationship to brake type is presented in the table below. The application codes are stamped on the wheels next to the valve stem hole. Note that some early to mid-year 1967 wheels were not stamped with the application code.

Most wheels are dated as shown below in the table and the picture. 67 and 68 FC coded wheels are stamped with an alternate date format: ddmmy (day, month, year), stamped on the rim lip but not next to the valve stem.

1967-69 Wheel Code Format K1y m (hole) dd aa where: K = Kelsey-Hayes 1 = Romulus, MI wheel plant y = calendar year m = month dd = day aa = application code K19 8 4 YH = a 69 Z28 wheel built by Kelsey-Hayes for Chevrolet on 8/4/69.

Wheels were painted black if full disc style hubcaps were ordered on the car. If the smaller 'dogdish' style hubcaps were installed, the wheels were painted body color. Rally wheels were painted 'argent silver'.

For 1967, rally wheels were required when disc brakes were ordered. This restriction was removed in 1968 (despite some 1968 dealer literature that indicates that disc brakes were required with rally wheels). Which means that in 1968-69, disc brake cars came with plain steel wheels, unless the ZJ7 rally wheel option was added (except for Z28 which included rally wheels).

While a promotional photo exists of a 69 Z28 with the narrower 68 15x6 DF wheels, this wheel was not used on 1969 Z28's in production. The initial 69 Z28 wheel was coded AD. The YH wheel was produced starting mid-December 68 and had minor modifications to increase clearance for the JL8 brake components.

 Year  Type    Brakes     Code/Size  Application
 ---- ------- ----------  ---------  --------------
 1967 Steel   Drum         B  14x5    Base
                           FC 14x6    SS
      Rally   Front Disc   DA 14x5    Base 
                           DG 14x6    SS
                           DF 15x6    Z28

 1968 Steel   Drum         FC 14x6    Base, SS
      Steel   Front Disc   XF 14x6    Base, SS
      Rally   Drum         XN 14x6    Base, SS
      Rally   Front Disc   XG 14x6    Base, SS
                           DF 15x6    Z28

 1969 Steel   Drum         FC 14x6    Base
      Steel   Front Disc   XF 14x6    Base
                           XT 14x7    SS
                           IF 14x7    SS (observed on early LOS cars)
      Rally   Drum         XN 14x6    Base
      Rally   Front Disc   XG 14x6    Base
                           YJ 14x7    SS
                           AD 15x7    Z28 (early)
                           YH 15x7    Z28 (late)
      "SS"    Front Disc   YA 14x7    SS    RPO N66 *
  
                                   * removed from Dec 68 order sheet