4500/5500 series Gmc/Chevy

[Renze]

I work for a Dutch company in the business of small drivers license truck conversions. We convert chassis-cabs to 5th wheel tractor, mostly the Mercedes Sprinter (which is sold in North America as the Dodge Sprinter)
the single wheeled light frame version goes up to 6,3 ton combined GVW and the dualled 5 ton version (which is derated as 3,5 ton to be be able to drive them without a big truck license) goes to 8,75 ton.

We get chassis cabs delivered from the dealers who have them converted to air brakes and a 5th wheel mounted, including the necessary homologation, at our company.

Dealers do not always know what to order, so sometimes we have to install chassis mods to make them safe.

From our experience with light vehicles pulling heavy trailers there is only 1 thing that determines the roadworthyness of such a 5th wheel tractor: On the vehicle options list, checkmark the biggest roll stabiliser bars you can get. !!!! period.

Also, we had several people that bought an airstream camper or a big horse trailer from the USA, that came to us to have the axles changed for air braked axles, or air over hydraulic brakes.
We have some USA built electric braked axles in store but we dont plan to sell them. Our company doesnt want to send people out to the road with electric brakes because it is rubbish, no matter what brand. The system itself, just doesnt work. We use air brakes with ABS, or Wabco EBS with ESP for the vehicles intended for a GVW of above 7,5 ton.


If you think that you need bigger brakes on your towing vehicle to get better stopping, i think you need to check your trailer brake system. The stopping power should come from the axles on which the actual weight rests, not from the towing vehicle. If the tractor brakes better than the trailer, the trailer will overrun it no matter how big the tractor is. (there are certain limits though )

 

[Turbys_1700]

If facing your delima I would go with a Freightliner or International unit. The bigger frame and air brakes are the real difference.

 

[Robbie Hegwood]

There are two points from the last 3 entreys that help me the most. Scottar thanks for the brake info mine is an 04, it does have monster disc all the way around and are in good shape. Also with ABS the truck is doing all it can. So i'm narrowing down on the trailer brakes. They are electric on all three axles. I will be going to the horse trailer dealer who installed my goose hitch to see if they have a better brake controller and anymore advice. My controller is a simple single gain dial type and I feel is the weak link.As of right now I have a hard time getting it set to my liking when towing. I would like a digital one to remember different settings for loaded/unloaded towing. Like I stated before the my truck is great I just want to be safe. I tell ya'll, between all our experience we can figure anything out.Thanks Robbie

 

[Bird]

You might want to send a private message to wroughtn_harv; one of our members who has put quite a few miles on his 2003 C5500 with the Duramax and Allison. As far as I know, he's still happy with it.

[We have some USA built electric braked axles in store but we dont plan to sell them. Our company doesnt want to send people out to the road with electric brakes because it is rubbish, no matter what brand. The system itself, just doesnt work.

Renze, I don't know just what size trailers and axles you're talking about, but electric brakes on travel trailers; both conventional and fifth-wheel work very well in the USA if they're properly sized and adjusted for the weight.

 

[Joe1]

One can find lightly used IH and Freightliner medium duty RV tow rigs for sale in Motorhome and Trailer Life magazines with few miles. They typically have Cat or Cummins Diesels in the 300 hp on up range and Allison 6 speed transmissions. They are set up for creature comforts in the cabs and are extended cab or gang cab configurations, many with utility bodies and 5th wheel arrangements. A few years old, they are priced at the new F350/F450 price range and have tow ratings of around 20,000 on up. May be worth checking out.

 

[Renze]

Bird:

Yes they do work if adjusted for the weight.... but that's the whole problem, load changes every time so they are in constant need of adjustment. 90% of the time electric brakes are adjusted wrong. Just compare this to what Robbie Hegwood just said.
With the air brakes we install, we mount a brake pressure adjuster that senses the suspension air bellow pressure and adjusts the brake pressure accordingly. Electrical systems can never match that performance.

Having to adjust your electric brake sensitivity while driving, has nothing to do with safe towing.

I've got a nice example here:

http://www.doornwaard.nl/images/94_foto2.JPG
(for this photo the yard dolly is under it to be able to move it by forklift)
It's an 8,5 ton trailer (intended for a vehicle with a combined GVW of 12 ton) with 5,5 ton BPW drum braked tandem axles. It has air suspension and load sensing brake pressure adjuster. It has hydraulic foldable drive ramps, which are also hydraulically adjustable in trackwidth.
It is towed by a 160 hp Renault truck, with a 2 ton empty weight and 3,5 ton GVW. This is a perfectly safe setup even though the trailer is much heavier than the truck.

It's just a matter of getting professional air brake systems and have a good anti roll bar on both rear and front axle of the truck.

 

[wushaw]

I quit working at the local Chevrolet dealer when they came out with those new trucks, they are the single reason I quit. Have you actually looked under the hood? OMG, where's the engine. Personally I would go with a Freightliner or International as wushaw suggested.

I too have seen under the hood of these and was not impressed with any of it.

 

[wushaw]

Robbie, I had a FL-60 with a 8.3 Cummins 310hp/950lbs tq and a straight ten spd tranny before the Pete I have now, that FL could turn inside any one ton and handle a heavy trailer with no problem, there are different models to choose from and alot to learn before you buy but they really are better than the C4500/5500 and fords F450/550.
You mention brake controllers, I had a Jordan in the one ton I had that worked great, it was set to how many brakes you had connected to the controller and is had amp draw not voltage output, amp draw will tell you if all brakes are working... a quick troubleshooting tool.

 

[Robbie Hegwood]

Hey Wushaw, That FL sounds like my kind of truck. What a powerhouse!! A tight turning radius would be nice, my F-350 is a crew cab,long bed,4x4. It takes two football fields to trun around, but tows like a dream{except for panic stops]. I will definitly look for the Jordan controller, sounds like the ticket. Thanks a ton for all the info. I make sure I get in touch before any purchases. Robbie

 

[ScottAR]

You might also look into the Brakesmart controller. Measures the trucks Master cyl. line pressure so it self adjusts.

Might also look into dexter disc brakes for your trailer.