Technical information

ManualsBrandsRoadmaster ManualsAutomotiveRM3477

Towing and Suspension Solutions

Whyaretherethree

‘hidden’bracketstyles?

Underneath the vehicle, every ROADMASTER bracket is a custom de-

sign, fitted to a specific frame and undercarriage. At the front of the ve-

hicle, there may be one of three removable extensions. Which extension

is used is determined by: 1) the structural integrity of the frame; and 2)

the vehicle’s styling.

If our Bracket Guide lists only an XL™ or an EZ Twistlock™ bracket for

a particular vehicle, that means our designers have determined that the

vehicle’s frame must be supported by a crossbar for towing. The crossbar

disperses the load across the length of the tow bar, and the front of the

vehicle — what our engineers call an ‘area load’ — a design which sup-

ports the towed vehicle.

The determination between an XL or an EZ Twistlock is the available

clearance at the front end of the vehicle — at the fascia and the grille.

The alternative to an ‘area load’ design is ‘point load’ design — the

front of the vehicle’s two frame rails act as the ‘points.’ If an MX™ design

is available, that means our designers have determined that the ve-

hicle’s frame is sufficient to support the vehicle during towing, and that

a crossbar is not necessary.

Some customers prefer the ‘cleaner’ MX design; however, there are

tradeoffs that sales representatives and service writers should be aware

of — four of our tow bar-mounted accessories (the Guardian, Stowaway,

the 4700 Tow Defender and Nixtopper™) cannot be used with an MX

bracket — which is why we offer a choice of both MX and XL brackets for

many vehicles.

Insert extension

and secure with

pin and clip.

Insert extension

and twist to lock

in place.

Insert extension

and secure with

pin and clip.

XL brackets

For both car- and motorhome-mounted tow bars.

XL brackets are the most universal — most vehicles have enough clear-

ance at the grille or fascia to allow the receivers to be hidden, and also

enough for the linch pin, which attaches each removable front extension

to the bracket.

All four ROADMASTER tow bar-mounted accessories (Guardian, Stow-

away, Tow Defender and Nixtopper) will fit on an XL bracket.

EZ Twistlock brackets

For both car- and motorhome-mounted tow bars.

EZ Twistlock extensions and receivers are designed for smaller vehicles,

with a limited amount of clearance between the frame and the fascia —

the Twistlock design eliminates the linch pin (which attaches the remov-

able front extension to the bracket) so the receivers do not have to extend

past the front end of the vehicle.

All four ROADMASTER tow bar-mounted accessories (Guardian, Stow-

away, Tow Defender and Nixtopper) will fit on an EZ Twistlock bracket.

MX brackets

For motorhome-mounted tow bars only.

MX style extensions and receivers are designed for trucks, SUVs and

other large vehicles with frames of sufficient size and strength to replace

the crossbar. Therefore, the crossbar is not required.

Because the crossbar (and quick-disconnect system) is not used, three

ROADMASTER tow bar-mounted accessories (Guardian, Stowaway and

Nixtopper) cannot be used with an MX bracket.

Also, the standard ‘EZ Hook’ safety cables for Sterling All-Terrain tow

bars must be replaced (with either #645 or #645-76 single hook straight

cables) — without the quick-disconnect system, there are no mounting

points for the EZ Hook anchor plates.

The crossbar compensates for the structural

integrity which has been lost in the transition

to lighter, more fuel-efficient vehicles. Most

passenger cars built after the turn of the century

fall into that category. They must be supported

for towing, for a simple reason — heavy gauge

steel has been replaced with sheet metal.

The crossbar is there to support the car,

not the tow bar.



bracket

Whythecrossbar?