Camel Back Mounting

[leversole]

Does anyone know for sure if the "elephant ear" style of camelback bolt pattern (to the truck frame) is the same as the later style where the entire center section is on the inside frame rail? From all of the pictures I'v seen, they appear similar.

[Vladislav]

If you mean this area I haven't seen any other bolt patterns of the same form but without Elephant ears to be mounted.

[jeffbyrne]

Short answer, No.

What you are refering to is the pedestal. There is basically three types of pedestal.

(1) The pedestal which had it's origins around the L models, and continued right up till the early nineties,(I think). The bolt pattern might be slightly different from the L model to the B model, and later models. This was a three piece pedestal, i.e. a fabricated X member and two cast trunnion brackets, which bolt to the outside of the frame rail,with five bolts per mounting point. (as in Vlad's pic). It appears this was the only pedestal used.

(2)Then sometime in the fifties(I think), there was a one piece cast pedestal which fitted entirely inside the frame. This pedestal was a one piece casting(X member and trunnion brackets).

This one-piece cast X member and trunnion bracket continued until about the release of the R model. The frame rail bolt pattern for this pedestal is totally different to any other pedestal. It used four bolts per mounting point of the X member part. This was a lightweight pedestal.

(3)About the time the R model was released, say 1965, a new one-piece fabricated pedestal became availble, this was a welded one piece X member and trunnion brackets, usually with a hollow spindle and rubber bushes. The bolt pattern for this pedestal is a different pattern the the other two mentioned pedestals (1)&(2). It has four bolts per mounting point of the X member. This pedestal superseded the one-piece cast pedestal (2).

(3a)Sometime in the early 70's(I think), another pedestal was used, I have only ever seen two or three of this type. It was a one-piece fabricated X member and trunnion brackets with a solid spindle, rubber bushed, with the same bolt pattern as the three piece fabricated X member and cast trunnion brackets pedestal(1). This type of pedestal used a large screw on cap on the end of the spindle, with two allen screw locking screws. I beleive that this was a heavy weight pedestal. It fits inside the frame like (3) but has the same bolt pattern as (1).

I hope I have'nt confused you, but you might be able to work out which pedestals you are refering to.

[B53]

My '64 B53 has the one-piece welded pedestal, as mentioned in (3). Actually, the mounting area of the pedestal has 5 holes in each mounting location, but they only drilled 4 holes in the frame.

[B53]

Should also add though, it's not camelback, but walking beam. Which leads to a quick question...my rears are only rated for 34 or 36k. Why walking beam? I thought that was typically only used on very heavy applications.

Kevin

[jeffbyrne]

Hi, B53, that would work if the holes were there for five bolts and only used four bolts, or if no holes in the frame and only drill four. But it wont work for a five bolt pedestal in a four bolt frame or a four bolt pedestal in a five bolt frame without drilling new holes, they would be very close to unsed holes, as the bolt patterns are different. I think you would weld unused holes. The fabricated heavyweight pedestals from the mid 70's on only used four bolts, but they were designed for four bolts. A fabricated five bolt pedestal is designed differently to a fabricated four bolt pedestal in the bolt hole location.

[jeffbyrne]

Hi Kevin, I think walking beam is also for rough terrain, which is probably considered as heavy.

jeff.

[57 bcr]

Should also add though, it's not camelback, but walking beam. Which leads to a quick question...my rears are only rated for 34 or 36k. Why walking beam? I thought that was typically only used on very heavy applications.

Kevin

Kevin,

Walking beam suspensions are used in mixer chassis ( like the B-53),purely for the reason that they don't allow the suspension to flex much (if at all) while the drum is turning.The company I work for used solid mount walking beam suspensions for years.Now the last bunch of Granite mixers they got in,were ordered with Chalmers suspension.I haven't talked to any of the drivers to see if the "flex" is really an issue. Al

[leversole]

I wonder when they stopped making the elephant ear type...I have seen them on much later trucks....

So if I were to get a cutoff from a 70's R for example, would the bottom row of bolts at least line up?

I guess I'll have to go and measure some!

[jeffbyrne]

I think they stopped using the three piece cast pedestal around 1990.

I'd measure up my bolt patterns, I think you'll find that pedestal (3a) in my description is the only fabricated pedestal that fits inside the frame that will bolt straight in where the 3 piece pedestal fits(1). Pedestal(3) is a different fit, only about 10" between the lower middle bolts. The cast pedestal is about 12". Outer bolts is about 20" for the fabricated one and about 24" for the cast one. The fabricated pedestal that replaced the 3 piece cast pedestal might be closer in the bottom row bolt pattern. I'm sure the top row would be way out. This pedestal used four instead of five bolts.

[maxidyne237]

The cast 5 bolt pedistal, or elephant ears as we call them had three types that I am aware of. The smaller set like you have were for 44k and down suspensions. This is the set that went away with the introduction of the fabricated sets in R models. Then there was the 55k & later 58k sets that had a larger elephant ear bolt pattern with larger bolts around 3/4". Then there was the 60k/65K that used even larger elephant ear bolts that were like 15/16" or even 1". These were used on 80K rears too. The cast iron elephant ear pedistals are still in use today in 58k and 65k Camelback suspensions. ( my bolt sizes are a little blurry, they might even be a little bigger)

[Maddog13407]

im just curious leversole as to why you would wanna change out your elepahnt ear type? jw. maybe i missed the boat haha

[leversole]

For a better gear ratio AND assuming something in the rears is causing the truck's bounce...

[Maddog13407]

thought you got 'new' hogs heads from Rudy after i got the transmission?

[leversole]

Yeah gottem...just thinking how much easier it would be to roll one suspension out, and roll another one in! If I do all of the work to change the carriers, still may have to totally rebuild and rebush the suspension AND put new wheels on it!

If I could figure out the source of the bounce and fix it, I'd swap the carriers out!

[leversole]

I just remembered the main issue...the torque arms are different types...I will have to find a set like I have and a set that fit the new carriers and weld them together!

[raydurr]

I bet your bounce is from worn out dayton hubs OR tire that is out of round,sometime only at speed. Tires seem to expand about 40MPH and above. Id try changing a PAIR out a time. Doing only one pair at a time. FIRST LF,then RF,thenLR and last RR. This is slow but Ive done it with great results .Good luck.

[Vladislav]

For a better gear ratio AND assuming something in the rears is causing the truck's bounce...

What the ratio do you have in your carriers?

Maybe I will have an interest for gears if you really get another bogie roll in.

[leversole]

My current ratio is 5:73...

[Vladislav]

Quit high for me.

Do you have flanges with 8 bolts around on the ends of pinion shafts for attaching propeller shafts or a U-part of a joint just out from the carrier?

As for vibrations I also think around hubs or rims/wheels are out of a circle.

You can try to jack each wheel, place some wooden block or any other static subject aside a tread area and look for a clearance turning the wheel over.

A source of vibration must be an out of round shape, disbalanse or axle play of any heavy turning part.

Propeller shafts also can though.

Maybe you have water inside the tyres? I met that issue at once.

[leversole]

Quit high for me.

Do you have flanges with 8 bolts around on the ends of pinion shafts for attaching propeller shafts or a U-part of a joint just out from the carrier?

As for vibrations I also think around hubs or rims/wheels are out of a circle.

You can try to jack each wheel, place some wooden block or any other static subject aside a tread area and look for a clearance turning the wheel over.

A source of vibration must be an out of round shape, disbalanse or axle play of any heavy turning part.

Propeller shafts also can though.

Maybe you have water inside the tyres? I met that issue at once.

I have the U Joints....

I can run each wheel in the air, no shake vibration etc...Tires are new, no water...

Thanks

Leslie

[Vladislav]

The U joints are not perfect for me.

I can use them also but with more rework.

How does the wobble when you apply brakes?

Doesn't it gets slow when you brake lightly?

You also can try to ride on wheels of one axle only.

Place blocks between the rodden axle and the frame but fix them good.

Need also to lock 3rd diff. It's not easy though, need to disassemble and put something to lock peanuts against moving.

[leversole]

Braking, coasting, or whatever, it still bounces at the 2mph range...

Having the local tire shop gather some rims to run only four tires to see if it changes...

I chained up one axle...got down the driveway and up the road but the chain slipped before I got to speed..had the brakes locked on the axle and it started dragging! Got it stopped before I broke something...gave up at that point...

[Vladislav]

You have one axle unspringed while try to run the other only.

Not a smooth way but can be resultive.

Try to fix the axle with straps for load. They're more flexible, can absorb shocks while running.

Use them more than one on each side.

Lock one axle with brakes isn't good. You force the interaxle diff to run with double speed instead of keep unmoving or turning over slowly while the truck makes curves.

Better is to lock it and than remove semi axles of rear propeller shaft.

Of course be too careful making these things.