Transmission Retarder vs Exhaust Brake

I only have the exhaust brake but I think the retarder would be good.

Only motorhome I know of not built on an OTR bus chassis with a transmission retarder is Foretravel.

Actually, there are THREE categories of supplemental braking on DP's:

Exhaust brake-- generally found on smaller engines/coaches. Adequate for lighter coaches.

Engine compression brake-- found on larger (smallest I know of is the Cummins ISL which is offered with it-- 8.9 liter). More braking HP than exhaust brake.

Transmission retarder-- most braking HP. But takes a little care, as you are turning momentum into heat in the transmission. Most come with 10 position joy stick for excellent fine-tuning.

The majority of city transit buses use retarders, so I am not worried about reliability. I would not shy away from a retarder, or an exhaust brake, both work well, and both are pretty reliable. Some prefer one over the other, me I prefer a trouble free rig, and would use either one or both.

gmctoyman wrote:
What is better, which works best ? A MH I'm considering has the transmission retarder is the reason for my question, I have no experience with either.

On a scale of 1 to 10.....if the exhust brake is a 2....the tranny retarder is a FIFTY!

Would be nice to know which MH your looking at. Gasser have transmission retarders, Diesels have Exhaust brakes or Jake brakes ie engine braking.

As a local fire captain explained to me, retarders are only good for short bursts like a city bus or a fire engine uses. Trying to use it to hold you back coming down a mountain pass would make so much heat in the trans that it would burn up.

Not true MCI used them in conjunction with compression brakes as per customer ordered. The units with retarders have larger coolers than without but heat must be monitored and have a manual over ride. Proper gear selection and break over speed is important.

ScottG wrote:
As a local fire captain explained to me, retarders are only good for short bursts like a city bus or a fire engine uses. Trying to use it to hold you back coming down a mountain pass would make so much heat in the trans that it would burn up.

Well Gang,
I'd have to agree with this answer. You see, in 30 years with the FD, we heated up a quite a few trannies on some of our long down grades and, forced heated stops. Once the Jake (Engine compression brake) became more available, we opted for them so we'd have considerably less trouble with our trannies. Then, we given a new kind of retarder for a demo for a year for try out.

That new retarder, called a "Telma" retarder, is the best thing since sliced apples. It works with electro-magnetic energy and, there's no parts that ever touch, just like a mag-lev train.

Anyway, if it were me, I'd opt for the exhaust brake. They work well, are fairly trouble free and, doesn't cost you anything in terms of potential damage due to heat. This is just an opinion.
Scott

I've got a transmission retarder in my Prevost and it works great. I've had 2 position exhaust brakes in the past that we're tough to modulate on a long grade down. Either too much or to little braking. The Prevost has a 6 position retarder and It"s easy to find the right spot. They do incorporate a large tranny cooler. In short I prefer a well designed retarder.

As other have said... heat is a problem. You get to the top of the pass and instead of cooling the tranny off on the way down you keep heating it... so a much larger oil cooler is used. It's a good system, just watch your tranny temps when using it on a long downhill.