Just wondering if you can add a jake brake to a 1975 4905 bus with auto trans.
I dont know how much it would take or if i really need it on a bus.
Yes the Jakes work good with the auto transmission but if you drive only in the flat lands it may not be worth the cost to you but in the mountains they are worth the cost for safety reasons.One of the GM guys will tell you if you have room for the taller valve covers in the engine compartment I am not a GM person and don't know if that is a problem or not good luck
Yup, you can have a Jake on an 8V71.
The hard problem is finding the valve covers for it...they are .9" taller.
However...
Email or PM me.
Is there room for the taller Jake valve covers between the tailgate and engine?
JR
jakes WILL require a modification of the tailgate on a GM
I have a 8V71 with an Allison automatic and it's equipped with a Jake. I finally bring my coach home next Tuesday down some long mountain passes (Coquahalla) so I can give a report on it then.. Can't wait, retirement and a Prevost we can call our own, hello highway goodbye fuel money.
fraser8 ... if you're going throu Merritt give me a call if you have time for a coffee 250-37eight- six 88 five
Great, I'd love to hook up with some local boys with buses.....
I have a transit with V drive, so the valve cover was covered by a panel in the tail gate. When I installed Jakes (I installed them even before taking delivery of the bus-since I live on the very mountainous west coast), the tail gate would not close. I just drilled out the rivets and removed the cover, and reinstalled fake rivets into the holes. Now you can see the valve cover, and it creates another outlet for hot air. I like the looks.
The Jakes on my 8V-71 works extremely well. When pulling my car, I weigh in at 34,750lbs. Coming down the northbound I-5 Grapevine which is 5 miles of continuous 6% grade, I have to switch between both heads and one head of Jake brake operation to keep from slowing down to much. Course, my injection and Jakes were precision adjusted by Don Fairchild in Bakersfield, Ca. Even if you live on the East coast, sometime in the future, you'll come west. Even some of the roads in the hills of the east coast can necessitate the use of Jake brakes. I can assure you, you'll use them in the very mountainous west coast. Good Luck, TomC
Fraser8, where are you picking up your conversion?
Lloyd
I'm picking it up in Vernon, it's the one that was for sale in Campbell River, a 72 Prevost. It was for sale for a while, with the high fuel prices we worked out a great deal we were both happy with. A very nice fellow who took extremely good care of the coach. It's in like new condition without a bunch of electronic gizmo's. I'm in the process of joining the BC Bus Nuts so I should see you all at one of the functions. If not a few of us should get together for a gab weekend.
Jakes work very well on the GM buses with automatics. As you become more acquainted with the looks of the GM bus, you will be able to easily recognize the bulge to the tailgate that some owners have added to make room for the taller valve covers.