Tranny Retarder switch/lever problem (Alli B500R)

[Zeroclearance]

My Dad just emailed me..  Here is what he said..

NOT probably  275F!  On hot days (90-95F) using retarder downshift from 6 to 5th to 4th (proper way)
and 2 clicks on the retarder after the downshift I've see the temp go to +375F.

[Dirtball]

BusWarrier,  I do what you say, downshifting at times. My tranny seems to be pretty good at doing this itself. Upon braking  and scrubbing off speed it will start downshifting on its own. I hope it's just the joystick. I'll start exploring access to the underside of the stick. I am not going to add the Jake at this time, I don't get to use the bus enough and the mechanic who had recommended it has moved away. With the TR working properly, I get by here in Pennsylvania. I have changed the tranny fluid twice and coach only has 45,000 original miles. It is a Custom Coach conversion from 1997.

[Busted Knuckle]

Dirtball,
Changed the fluid twice already and the coach only has 45,000 on it?
Wow that's quite excessive. With normal ATF in them it's recommended @ 30,000 and Transynd (or equivalent) it's 90-100,000 miles between service.

We use transynd and change the filters while changing fluid and once in between.
FWIW
  BK 

[jack14r]

I have an Allison in my bus and I have never seen temperatures above 225 coming down mountains and I rarely use the brakes,I see a lot of comments by those that have heard of very high temperatures from others,but not their actual experience.

[Dirtball]

Finally going to the shop next week to hook the Allison up to the laptop.  Tech says it can be just a bad joystick- which may even be able be adjusted back to Normal operation,  or it more frequently is a bad solenoid in the tranny. Solenoid requires dropping pan from tranny.  I will post an update in a week or so. My left hand has been getting tired holding the joystick forward when I am coasting.

[luvrbus]

My B500 behind a series 60 will reach 350 degrees on a warm day with the retarder,I don't use it much the heat scares me on a B500 so I use the Jakes they work better anyways

[HB of CJ]

Documented?  Dunno about that.  PEM if you want to.  Involved a 42,000# Type One fire engine coming down (North bound) Eye Five South of Bakersfield CA at 75 mph with the tranny retarder in the max position.

Infamous Ridge Route.  Non happy combination of non fortunate events.  Taxpayer job.

Never touched the brakes.  Roasted the tranny and other stuff.  Big repair bill.  The driver never knew better.  Lack of training.  Stupid also.  Had no idea all that heat had to go somewhere.   Did not care either.

[wg4t50]

My setup with the ISM500 & Allison 4000 with retarder, also have the temp readout on both the trans sump and retarder.  Using the Transynd (?) am told max retarder temp s 300 and sump 250.  No Idea what is correct, am told via the Allison Lube Engneer (retired)
With practice can control temp, keep around 220 for retarder and good control braking effect.
My coach is 30,000 lb when no toad. Yes you can run the temp way up real quick.
A lot more effective than a 8V-92 Jake setup, no Idea about the four stroke setups.
Dave M

[Scott & Heather]

My retarder on our new to us 102c3 was stuck on and I couldn't figure out why I kept overheating. Jumped out of the bus on the side of the road and my buddy pointed to the smoking tranny pan. Gunned it with laser temp and it was 290 or so. Climbed into engine bay and spun the air regulator for the solenoid all the way to 0 psi. Problem solved.


Sent from my iPhone using Tapatalk

[blue_goose]

I know this isn't the same as driving in the mountains, but most all city buses have retarders.  I have driven buses with 8V71, 8V92, series 50 and series 60 with jake brakes.  None of these had as much power holding back as a retarder.
I drive a city bus at Disney World with a retarder and have not had any problem with the transmission.  Some of the buses have the retarder come on when you take your foot off the throttle and some when you put the brakes on.  These buses stop an go all day every day and every stop the retarder is on.  The retarder shouldn't be putting out any more heat coming down than the engine did going up the hill.
Jack

[luvrbus]

The B 500 won't even sound the alarm till temperatures are 275 degrees in the retarder or 330 degrees in the sump.

Allison says 350 degrees intermittent use won't hurt the transmission with synthetic oil but if the alarm sounds it's best to pull over for a cool down,the B 500 is a transmission for buses only they are different  

The price of a B500 I'll go with Jake's my 60 series has fanatic Jake's and the B500 does a good job controlling them so the retarder is just there for me.The B 500 in the bus is low miles John 316 and his family paid somewhere around 14 grand in Fl for the transmission and I want it to last so I don't use the retarder     

[LuckyChow]

FWIW, our transmission folks tell us that the retarders in our B400 transmissions are designed for stop and go in our normal transit service around town.  They seem to work good for that as we rarely have any trouble with them.  However, they have cautioned us not to use them for coming down long, continous mountain passes, as they were not designed for that type service and will overheat.  Apparently the fluid is not sent to the transmission cooler as long as the retarder is activated (being used). 

[John316]

The price of a B500 I'll go with Jake's my 60 series has fanatic Jake's and the B500 does a good job controlling them so the retarder is just there for me.The B 500 in the bus is low miles John 316 and his family paid somewhere around 14 grand in Fl for the transmission and I want it to last so I don't use the retarder     

Hey Clifford. We would use the retarder momentarily in heavy traffic. If we needed that bus to stop on a dime, we would have the retarder switch on - plus we always ran with the jakes on. As soon as we used the retarder, we shut if off, and let things cool back down. I always got concerned when I saw the temp starting to rise. I never let it get over 300.

[mikelutestanski]

hello;    FYI    to answer one statement:    the retarder fluid always goes thru the cooler, that is the basic circulation path. When the retarder is activated via the air cylinder the extra fluid is pushed into the retarder cavity where the fluid is absorbing the energy from the driveshaft creating heat.  The temp will go up however if your engine has adequate radiator capacity the temperature will go down as the heat is dissipated thru the bus radiators.
   I WOULD SUGGEST YOU BUY 2 PUBLICATIONS BY ALLISON, ONE IS B???  PRINCIPLES OF OPERATION AND THE OTHER IS THE SERVICE MANUAL. THE OPERATORS MANUAL IS ANOTHER USEFUL GUIDE. THESE USED TO BE FREE BUT PROBABLY NOT NOW.   A PARTS MANUAL GIVES YOU PICTURES OF THE PARTS INVOLVED AS LONG AS YOU CAN DECIPHER ALL THE NUMBERS.
 
    My retarder went on the fritz this spring. The solenoid for the retarder was showing a short. I changed the relay and as it turned out the connector was the actual culprit.  I did not need to get into the actual relay cavity because the connector was shorted out..  So the lesson is to do your troubleshooting up front as completely as you can.  Wiring and connectors are one major source of problems according to some of my sources so inspect the wiring and connectors carefully.
    Sammy told me once when I was trying to decide what to do with the b400R.  he said that you do not use a jake with a retarder because the bus will stop so quick as to put you thru the windshield.. his words not mine..I had the option of adding the jake to the L10 but declined in favor of the retarder.
      I have a B400 with an L10 . I transplanted the L10 B400R complete with all accessories to my mic 7. The motor worked before and after. The radiator capacity is the same as an 871 so I have extra cooling capacity.   
  I put a temp sensor on the input to the cooler;   oil side (it is on the outside and covered).  My normal temperature is around 160  .when going down long hills I have seen the temp go to about 220 . It never stays up long and is normally at 160.
During our summer trip to canada the  average temp went down esp. around lake superior where the lake temp is 41 degrees and the average air temp is in the 60s..
   my bus was featured in may 2011 , the complete story and pix are there if anyone is interested.
  WE try to take a 2 month trip every year.   This year was 7000 miles and 2 years ago 8000. miles. 

    So far with the L10 we have about 40 thousand miles and average 7.4.Mpg.  I really like the B400R tranny.
i did not have any experience driving big rigs ..I learned by doing and trying to get advice from others. I have a total of 90 k miles  of driving time on this bus now.
  Ted Keating sales in NC deals in allison parts and will help with some of your questions....
   The actual problem here with the retarder joystick can be answered with the computer hooked to the transmission and cycling the stick. the computer will show what the stick is doing. you can measure the resistance but the computer is the best source because it shows what the computer is seeing.
 
SO everyone has an opinion and this is mine. flame out if you want and I will do what i did before.. retire for a few years... 
  Regards and happy bussing.
   mike
   

[luvrbus]

Only a small portion of the oil goes through the cooler with a retarder depending on the level ,the valve traps the oil in the retarder cavity working against the paddle wheel that is what gives you the retarding affect.

I haven't seen a modern bus manufactured in the last 5 years that didn't have a integrated Jake on the engine with or without the retarder and most retarders no longer use the joystick all the casino buses here have both Jakes and a retarder MCI,Prevost or Vanhools

They use the retarder in town and the Jakes coming down from the pass on Az 68 from Kingman to Laughlin a 8 mile 6 % decent