Jake Brake?

I have a 97 45' Liberty, Allison Six Speed equipped with a Transmission Retarder - I live in an area surrounded by substanial hills in most any direction, and sometimes feel the retarder is inadequate for slowing the coach on the down hill side- Question - has anyone added a Jake Brake in combo with a retarder, looking for someone with experience here, is it worth pursuing to try to add a Jake or is it cost prohibitive? or just buy brakes, and change the tranny oil often.
thanks is advance
Roger

Roger,

Try posting on the other site also. The population is bigger and that might help to find the answer.

BTW, installing a Jake is likely not a difficult job but it will entail disassembling your rear drawer units and gaining access to the entire top of your engine because all the work entailed is under the valve cover.

Jon

Roger Dodger,

I had a retarder on a Foretravel and it worked pretty well except is really cranked up the trans temp when engaged. The Jakes really do make a difference, but you may look into PacBrake to see if there is an application for your series 60 using an exhaust brake. That way you wouldn't have to get into the engine, just plumbing into the exhaust.;)

Tom -(and JON) thanks for the info - but I may not get to hot to pursue it just yet. Reason being I exchanged an email with the All knowing amazingly full of useful knowledge anal Burger king JON. He suggested or I should say commented that he would put his retarder in the 2nd position and leave it - and tap the brake as needed and keep the temp down on the tranny. I went down I-77 Fancy Gap (VA into NC) Monday Night and tried it - I believe Jon is on to something. I decended at about 55 to 65 with no major effort on the brakes and the temp never exceeded 230 degrees outside air 69 degrees.
In the past I would increase the retarder position to 3, 4, 5 and the temp would climb then I would release the retard completely, then the tranny jerks like crazy

I must confess I don't know how the retarder actually works but appears to perform better when left in a certain position until temp retuns to normal.
Maybe some others could join in and as we say in the south Esplane that.
Roger that

NOW are you ready to give me the keys to that M3, and step aside for the bling contest?

The retarder has some characteristics I would like to understand more fully.

For example, if you put the retarder switch "on", but leave the little lever on the steering column in the "off" position a brake application will show the transmission temp increasing because the retarder comes into play even though the lever is not in one of the positions. Apparently the harder you hit the brakes the more retarder is applied in that case.

I found the retarder is more effective if left as Roger prevously described it at holding the coach back but not overheating the transmission. It is when the retarder is applied when speed is starting to build that it does not seem as effective and a higher position is required. That is when the tranny gets hot. Adding brakes almost always sends the temp higher than I care to see it.

I still wish I had a jake.

http://www.hankstruckpictures.com/pi..._for_atlas.jpg

Jon wants a Jake brake to compete with the Carolina Condo, a famed tractor known on the CB channels at night (Gasp). That way he can let it rip near cemeteries, school zones and churches.

I KNOW the Fancy Gap road! That is near the ill-fated attempt to talk the Virginia State Trooper out of my radar detector-->detector incident.

It is also the location (headed south) where the crummy Liberty lost air pressure due to a blown brake chamber on the right rear tag axle. The view from there when you are under control is fabulous; a little more exciting when the coach is speeding up and the corners seem to be coming faster and faster.

It seems that the 8V92's handle the downhills easier with the retarder working, as they are operating at higher RPM than the various-colored, 'other' engines with which we are becoming more familiar.

I read somewhere that if you install a Jake (and there was a picture with the plumbing required to go along with it) that you would have to redo your exhaust system/muffler, etc.

Most of the pro drivers like JW and others say that they will never drive a tractor without a Jake due to its abilities to slow down a heavy load.

As to the Fancy Gap road, which we travel at least a few times a year, we come over the top headed south in the right hand lane a tad slow, downshift and let everyone else go by. You can't keep up with the tractor trailers, as they don't have the delay in cornering and can handle the corners better.

An even better tip is that if you stop in Fancy Gap, they have the best prices for diesel in the area, and the truck stop there always smells like bacon. And, Virginia bacon as well. Probably not as good as Mango Bacon, but, well, you're not in Alexandria either.

And that's the report from the darkness of Maine for the moment.

EOM
10-4

If you modify your coach to add the jake brake you do not need to make any exhaust modifications.

All changes are in the head under the valve cover.

All a jake brake does is use oil pressure to open the valves at the top of the compression stroke. What is then happening is the stored energy from the compression stroke is dumped through the exhaust and it does not contribute any power to pushing the piston back down. If the exhaust valves were not to open the compressed air would push the piston back down so no engine braking would be provided.

A Pac-brake operates on a different principle and it essentially chokes off the exhaust. That does require exhaust modification.

I cant seem to figure out why our jake wont work. The high idle kick is also inop. All components are there. I,m thinking its an electrical not mecanical problem. 8v92t Jooooooooe camper