Why a Cab Over?

[10thumbs]

Hi Guys,

If you don't mind there are several questions I have about big trucks in general.  I think I might like building one, at least the tractor part, or even start with just a big motor.

So, what is the difference between a cab over and a machine with a long hood?  Why choose one over the other in real life?

Take for instance the logging videos, I don't seem to see a cab over hauling logs.  Do the 2 types have different motor combinations?

Maybe a factor of handling and visibility?

I'd appreciate some clarity about this.

Thanks guys, Michael

[Petetrucker07]

Back in the good ol days of trucking. The length laws are why the cabover and 40 foot trailers were the common site. Then the length laws changed allowing for "hoods". 

In the mid 70s into the 80s, even 90s, it was a matter of preference and still, some length limitations. Then some say it was saftey, some say this and that. The length laws were changed yet again around the mid to late 90s allowing the conventional to pull 53 foot trailers. 

My preference is more toward cabovers, but with California's emissions laws gettin ridiculous, there almost isn't a choice anymore. I've heard there is a law requiring a certain distance from the bumper to steering wheel, but I'm not informed enough on that to say anymore. Here Ca, there are a few companies pulling 57 foot trailers and a cabover is the only way to pull them.

Kenworth still makes COEs, just not in the US. The Freightliner Argosy was last COE available here. 

The drive trains are the same, just certain parts, like shift linkage, steering. 

I know of one logging truck. It's this months cover truck of 10-4 Magazine. Here's a link..

tenfourmagazine.com 

Hope this started to answer your question.

[KJ790]

Yup, it used to be all about length and weight. Cabovers were shorter and often times a little lighter. Cabovers turn sharper and are nice for getting around tight cities or into tight spots. Most people prefer the look of conventionals, and most say that they ride smoother because the longer frame allows for more flex, which absorbs some of the bumps. There have been some cabover log trucks, dump trucks, and car haulers around, but they are not very common.

[10thumbs]

Clayton, now I'm slowly learning why you're not happy with some truck lawmaking.  It does seem irritating.  Thanks for the link. 

Thanks KJ, I was kind of thinking the cabovers might turn corners easier in cities.  I like the look, and can't really say I have a favorite. Both types just exude power, and I just read some Diesel info, 1500lbs. torque is serious power.

I'm enjoying my truck adventure.

 

[Greg Myers]

Not photo shopped, can't find the site though  

[10thumbs]

Mr. Myers, it looks as though you've in the meantime learned to post pics.

What does that have to do with this topic?

 

[Mike77]

Although I never had the opportunity to drive a COE, I believe comfort had something to do with them falling out of favor as well. In addition to the longer frame KJ mentioned, in a cabover you're sitting directly on top of the front axle (slightly rougher ride) and you're also sitting directly above the engine (year-round heating, even in summer! ).  Since cabovers are few and far between these days it's a real treat to see one. The white & red Transtar II I saw the other day pulling a flatbed was gorgeous, but unfortunately traffic didn't allow me to photograph it.

Edited November 22, 2015 by Mike77

[Petetrucker07]

It's kinda funny. It's been about 10 years since I climbed in a COE. It would take me a second to remember which foot to start with to climb in it. The last time I climb in one, I almost fell out because I started with the wrong foot. 

Here are my favorite COEs.

A Pete 362

A Freightliner and Pete 352

A Kenworth K100 

And a Kenworth K123 

I'm a little more partial to the K123. When Dad started driving, he bought an old P.I.E. K123 day cab 2 axle, 6V92. Painted silver with red stripes. I have some very fond memories of that truck. I remember sittin in the passenger seat, I still remember the red glow from the turn signal by the windshield and door. Someday I'll be building that truck in scale. But only from memory. There are only a couple Polaroids of that truck, front facing only.

[Aaronw]

Cab Over Cab Forward trucks also allow for a shorter wheelbase which in turn gives a smaller turning radius. Cab over trucks are still very popular for medium duty delivery trucks and fire apparatus due to their better maneuverability on congested city streets. 

[10thumbs]

Thanks guys for the insight.

Clayton those are fine looking trucks there.  The Pete 362 does look really high.  I'd need an elevator.

[Petetrucker07]

Those are cool. Purpose built to do something that's mass produced cant. I think that's how they can still be produced despite the supposed bumper to steering wheel distance, vocational/emergency vehicles. Trash truck type trucks are produced here by Peterbilt and Mack. Tight, city driving. 

[Petetrucker07]

Micheal, that 362 is tall. So is the CL9000 Ford.

[Force]

Over here in Sweden and Europe the length regulations has killed off the conventionals and all truck manufacturers are only doing cabovers as the demand for conventionals wasn't enough to continue production.
Scania stopped making the T series 2005 and Volvo stopped making the NH 2006, Volvo still do conventionals for the North American market.

Edited November 22, 2015 by Force

[Harry P.]

Cabovers are still very popular in Europe, in fact they're probably the most commonly seen big rig style.

[Petetrucker07]

Like Hakan said. The length laws across the pond are very strict and short. Me personally don't care for the look of the Euro trucks, but they are getting more stylish. There are a few I've seen that very nice. The Asian trucks are different looking. They can be done up. They tend to be gawdy to me.

[tbill]

that red and white k100..............drool................my gosh that's sexy!

[purepmd]

Clayton and KJ hit the nail on the head. Back in the 1960s, a class 8, on highway truck could only be a maximum of 57' and weigh 72,800 lbs. The easiest way to get the most payload within these regulations, was to put the driver over top of the engine, and keep the wheelbases under 190 inches. The cabover ruled the road, especially when you factor in all the restrictive bridge laws that could, and would be enforced. Each state setting something different.

Look at the AMT truck and trailers were all modeled off equipment of the day, 40 footers, and short wheelbase cabovers.

l did the math, and it was 33 years ago, I drove my first truck. It was a red and white, white freightliner FLA. Catpowered and 15 speed equipped.  

One of the best things about cabovers is the visibility. You are not looking around a hood, or exhaust, or sleepers. You are right overtop of the left steer tire, inline with the side of the trailer. Backing up was never easier. Blindsiding was a bit tougher, though.

Clayton, you tastes and mine run along the same lines. Freightliner FLA, Pete 352, 362, and Kenworth K100 are my favorites. With honorable mentions going to the CL9000, IH9670, Road Commander II, Astro 95, and  IH 4070B.

There ain't no feelin' like Cabover mobilin'.

 

[Petetrucker07]

Mark, there sure aren't many of us left. I know there are truck enthusiasts, who don't and may never drive, kinda like the guy from American Trucker. But true to the core truck drivers are few and far between anymore. Someone who drives for the love of putting her in an easternly wind and watch the sunrise on a cool spring morning. Or skirtin around an approaching storm watching the clouds pour over the tops of the mountains. Or the best site, the sun set when your about a half hour from home. Or sittin in the So Cal summer traffic doin your official duty of leg checks and cleavage patrols. 

I'm gonna be stopping by my buddies house here in the near future to see how much he wants for his ol K123. It's a got Big Cam 400, 13 speed, Alcoa steers, chrome 2 hole drives and a straight set of smokin 6s. 

I've been told I'm stubborn. There's worse things to be. I'm a truck driver, will be till I take my last breath. I just hope I don't have the truckers retirment. Pulling my cold body out of the truck. I'm gonna fight for my chicken lights and mudflaps weights, I'm gonna help a fellow driver when ever possible and keep my CB turned on and answer the bear reports whenever I can.

I got off topic and on the soap box. Sorry!

Channel clear, 10-4 

[10thumbs]

The big Euro trucks are quiet as heck too.  I know when you pass one that's doing 60mph, you don't hear it.  Modern looking and sleek, but no character in my opinion.  Those big trucks shown here are just good looking and purposeful.

The red and white K100;  What extras has the owner added?  I'm sure lots can be assembled from the factory, but what is on there that is beyond the base factory delivered model?

[Petetrucker07]

What is added...

Bumper.

Trim pieces on the bottom of cab and the top and bottom of the fuel tanks.

Lights.

Deck plate.

Air line box.

Rear fenders.

I imagine there is a rear bumper loaded with lights too.

The suspension has been lowered.

And the level of polishing done. Factory polish jobs do not look that good.

There is probably more. If you image search Ownby Trucking, more pics will come up, along pics of the truck this replaced. It was a 362 Pete. I've seen that in person many years ago at a show.

[Greg Myers]

Mr. Myers, it looks as though you've in the meantime learned to post pics.

What does that have to do with this topic?

 

COE 

[10thumbs]

Clayton that's quite a list.  Probably buy a home for the amount of extras on that rig.

".... Or sittin in the So Cal summer traffic doin your official duty of leg checks and cleavage patrols. "

Always a good thing to see what's coming, am I right?

 

[Muncie]

The Surface Transportation Assistance Act of 1982 changed the whole heavy trucking industry from cab-over to to conventional.  It replaced state regulations that limited overall length with national requirements for the length of the trailer on interstate and designated highways.

When things were limited by overall length, the cab-over equation was shorter cab equals more trailer, more trailer equals more revenue.  When the DOT dropped the cab from the equation, the industry changed over to conventional cabs  - most drivers preferred the conventionals.

Edited November 23, 2015 by Muncie

[10thumbs]

Thanks for the insight Steve.

If I understand this right,  the allowed length of the vehicle excludes the cabs.  Only the trailer has length limitations.   All states comply.

Thanks.

[Muncie]

correct, the size regulations for the interstates and designated highways regulate the length of the trailer and do not include the cab.  There are still some roads off the national network where the state overall length rules for the combination still apply - but the state rules see limited enforcement so the national regulations basically apply there also... of course we're talking regulations here so it's more complicated, but that's the basics.

Under the cab, there isn't much difference between a COE and a conventional - same engines, same chassis, same suspensions, same electrical, same brake system... different steering and shifter, longer wheelbase of course.  Some of the higher horsepower engines, especially with later emissions engines, are not be available in a COE because available space under the cab isn't big enough to handle the cooling systems.  Current demand for high horsepower and lack of space for an adequate cooling system basically put an end to the production of COE's about 5 years ago in class 8 (over 33,00 pounds) heavy duty trucks.  COE's still have some applications in the smaller medium duty classes.