Twin Steer Kenworths

Ipec had one , or a subbie.

Been away for a while so a few posts to answer....

Whether built in the US or locally K12x is single steer and K14x is twin steer.

First imported twin steer looks to have been about 1967 for Eric Ballard in Queensland, used on stock. Of the remaining imported ones it looks like about 6 were specced heavy for outback work (including the 2 Bell Bros ones) and a couple specced for metro oil company work. These were all in the Seattle number series - 6 digits beginning with "1".

Judging by some old communications I saw at Bayswater there was some development work required to get both the steering geometry and power assist sorted to suit Australian requirements.

With local manufacture (6 digit chassis numbers beginning with "4") twin steers became more common,particularly in oil company work and overnight express plus continued application in heavy road train/off highway work.

To address mammoth's comment on steering - up until about the mid 70's they used Garrison assist with a ram on each axle mounted between the axle and the tie rod and the control valve in the drag link on the driver's side. There was then a development with single point Garrison, retaining the control valve in the driver's side drag link but using a single ram acting on the idler arm on the passenger side between the two axles. Don't know if this became the standard and, if so, for how long. The final evolution in the 70's used a Sheppard integral power steer box on the driver's side with a slave unit on the passenger side with the pitman arm acting as the idler between the two axles.

Beyond the 70's I don't know.

I hope Grumpy will step in and add to/correct the above as we share a similar period at Kenworth and his memory may be better than mine. And sorry if my terminology for the different components isn't quite right but I'm sure you'll get the drift.

That photo of angle-iron's looks like the unit specced for Esso to minimise tare weight. As well as the Alcoas it's got alum rails and a 6V71.

The IPEC units from the mid 70's were distinguished by being twin steer and single drive - 6x2, Chinese 6's or whatever! The first batch were built with torsion bar on the drive and 6V71's. Wasn't long before it was pointed out by the drivers that their MAN's were quicker and lot less scary to drive. So they were retro-fitted with 8V71's and conventional springs on the drive. There was an internal KW Engineering directive never to fit single drive torsion bar suspension on overnight parcel vans again.

Found it!

Imported torsion bar twin steer - before and after conversion to 6x4 in use with B&M.

Gr8 info Jimbo

FWIW
Chadwick Demolition from Rosebud Vic
Had a 8x4 KW Alloy chassis as a Tipper
may have been X oil co

cya

...thanks for the very informative posts Jim .. as well as the Esso connection with the 8X4 aluminium chassis rigids, BP had a couple of them and one for Golden Fleece also.... all Bayswater manufactured back in the day

... the Golden Fleece unit was ch/no 400068 and this particular truck in the photographs is very early...evidenced by the Seattle air cleaner cab brackets with the four clamps....cheers fellas

The twin steer torsion bar buggey,

Yeah, slimline cab , 903 ,9 speed R/R.

In the middle seventys i drove that thing up from Bayswater to Lansvale where

it sat around for a year or 2 & didnt do much except go to the truck show

at the Yenora wool sheds.

I wouldnt like to think what it would handle like with a load on, but as cab chassis it was a bit

dodgey. A bit of rough road & you would have to stand up in the saddle.

At that time it was painted a dull red colour ,sort of like a red oxide under coat.

By the previous photos i see it was also yellow at some stage.

All of a sudden it just vanished & i wasnt sure what happened to it, except

some one said the steer bar bit was removed & a single steer spring axle

fitted, then went to work as a 6 wheel tipper.
..
As i recall ........................Billy.....................