Alison Tranny Retarder vs Jake Brake

I agree with Jon about the brake lights coming on. The Jake in our busses (8V's are the worst :( ) are not nearly as effective as they are in a truck and no truck that I've ever driven has jake actuated brake lights. I admit I don't have the trucking experience of many of our esteemed Poggers so I might stand to be corrected. Tom? Joe?

Last year Beverly was descending a long grade in the bus, we were being followed by an acquaintance (Winnebago). At the end of the day I was approached confidentially and told I might need to counsel my wife about riding the brakes. Needless to say I set him straight very quickly and ever since have been meaning to try and disable this feature.

This discussion prompted me to call Prevost yesterday morning. I was informed by one of the area service managers that this is a common request and he promptly informed me that removing Relay 76 labled "Jake Brake Signal" in the engine compartment electrical panel would disable this feature. I can't imagine he would have shared this information with me if Prevost feels this is a significant safety item. Needless to say, I now have another spare relay. Of course it's very possible that different models and years may have varying relay numbers but would bet the labeling would be correct.

BrianE
94Liberty XL

Brian,

The older trucks did not turn on the brake lights with the jake, the newer ones do. My Marathon does not turn on the lights and I wouldn't have it any other way. I like the jake function while on cruise control. My chassis is 10 years old and if the brake lights came on with the jake, I would lose the cruise. I suppose the newer buses have become more electronic where the jake/cruise/light are all controlled by the computer and work in harmony.

During the Tampa RV show I stopped at the Allison Transmission booth, and asked the Allison Transmission Man, the question I posed to you guys earlier in this Post.

Retarder or Jake Brake.

This information comes straight out of the Allison manual and agrees with pretty much everything everyone out there has said, but I thought I would pass on the information as it is 100% Reliable. :)

The cost of owning and using a Transmission Retarder DOUBLES compared to the ownership of a Jake brake. But I guess you all knew that :rolleyes:

Fluid change using Transynd is 300,000 miles Normal Operation or 48 Months
Fluid change using TES389 is 150,000 miles using a Retarder or 48 Months
Fluid change using Transynd is 25,000 miles Normal Operation or 12 Months
Fluid change using TES389 is 12,000 miles using a Retarder or 6 Months.

The filter change is also dramatically different ( Cut in Half ) depending on Retarder or NOT.

The problems of overheating, and causing major problems apparently has been solved or eliminated, because the Allison Man said they had experienced no problems recently??? Even Rick Thompson insists on the Retarders and believes in them, and puts Retarders on all of his new Thompson coaches.

Enquiring Minds want to KNOW

Gary S

Gary: You may wish to edit the maintenance schedule to reflect Dextron, not transynd requires 25000 mile changes and Dextron will never go 150000 miles with a retarder.

Gary, Please check your post for typos and weather you said what you meant. If everything is correct I will be back for an explanation. :D:D JIM

I think Gary just transposed fluids in his tabulation.

But re-reading the post brings something to mind that the pilots on this forum will appreciate. We are guided by limits. We have limits for airspeeds, oil temperature, cylinder head temperatures, etc.

These limits are exactly akin to the Allison transmission limits for temperature.

There is not a pilot on this forum, or any other for that matter that runs his plane at the limits unless he is attempting some speed or other records. If our transmission temperature limit is XXX, the further we are from that limit during normal operations the better it is for the life of the fluids and transmission. They are saying that without saying that explicitly by classifying the use of a retarder as severe duty.

I agree the transmission retarder might be more effective than a Jake, but I want my Jake because every time my retarder kicks in I know I am taking money from my pocket and I am having an adverse impact on my fluids and transmission.

The comments from the Allison Tranny Man reminds me of the comments of one my former employees: " I ain't lying this time".

Quote:

---

Originally Posted by Jon Wehrenberg

Gary: You may wish to edit the maintenance schedule to reflect Dextron, not transynd requires 25000 mile changes and Dextron will never go 150000 miles with a retarder.

---

I tried to copy the Schedule Maintenance Log out of the Allison Info packet but could not find a way to copy it into this Post. I will try to correct any misinformation I gave last night.

Two types of Filters Gold Series / High Capacities

The information I posted yesterday was taken from the High Capacity Filter Information not the Gold Series, which I am sorry was very misleading.

Jon, you mentioned Dextron, but Transynd or TES295 is mentioned all over the information packet as the Fluid used ? The Optional fluid and changed more often fluid is TES389 or MIXTURE* as stated in the booklet?

The mileage (300K) I posted was taken directly out of the information provided for the 4000 series High Capacity Filter info.

But after I got your reply posts, I got on the web like I should have gotten the first time and found this VERY INFORMATIVE AND HELPFUL WEB SITE. This should help clear everything in my post up, and correct any and all MisSpeaks that I may have entered last night.
http://www.allisontransmission.com/s...rval/index.jsp

Sorry I was trying to be helpful, but just confused the issue. :o My MAIN reason for posting was to Strengthen the advantage of the Jake vs the Retarder due to the Higher Maintenance cost.

Gary, quite the contrary. You did not confuse anything because of inadvertandly transposing a listing. We know what it meant and thanks for posting.

I am using the common terms of Transynd which is a proprietary synthetic (Castrol I think) and Dextron, the common ATF.

Gary, Have no fear the typos are inconsequential. Since we are trying to be exrtemely accurate I just wanted to mention it in a friendly way. You know 300,000 mi. from now I might forget what I now know. When I go to look it up I just want the data to be right. Thanks for going the extra mile to be helpful. :)JIM

Having just recently experienced with a lot of miles both the Jake (H3)and The Retarder (Libery Xl1) (or The Retardo as the Mangoettes call it). I have to comment.

Retarder Hands Down Winner:

Performs as intended in slowing the bus down. Does a much better job than the Jake. I can come off the interstate into the decelaration lane and use the Retarder without having to touch the brakes until it drops into first gear. I can't do that with jake. With the Jake I'm using the brakes a lot more than with the Retardo in the Liberty.

I know all the worries and comments about fluid temperature, and until a month ago when Jon posted here I thought the magic number was 230, but even out West, with some planning, I rarely exceeded 230. Now I know this means more frequent fluid changes, but I think this is a small price to pay. The bus definetly stops quicker and with less brake action with the Retarder.

I wish is was on the new H3.


Mike

Mango Man,

Are you sure your in the high position with the Jake? Turbo boost will tell the story when comparing the low/high setting.;) Your also probably heavier than the poor ole long forgotten Mothership I.:D

Trukman,

Definetly in the high position. You're right, weight be a factor, but there is a dramatic difference.

Mike

Strictly an opinion here, but a Jake is sensitive to high RPM. It wants high RPM to be effective and with the Series 60 which in our buses is biased to let the economy mode be primary it is possible the Jake is working at much less than its full potential.

As to the suggestion the retarder output temps are not exceeding 230, I believe that but also know when the retarder is on and brakes are applied the temps exceed that. The cynic in me suggests that is why the newer coaches with retarders do not have a transmission temperature gauge. That information is available, but the driver has to scroll down through pages in the ProDriver to access the information and in this marketplace few drivers even think about these things.

Hey Mike, I think you can have a Retarder added to your new H baby, if you really wanted to? Somebody feel free to correct me if I am wrong about this.

I tried to find some info on the Allison Transmission web site, to send along but could not find anything about the retarders at all?

Gary S

If you don't believe your jake is slowing you down as it should and if it is RPM sensitive as Jon says, I believe Allisson can adjust the Jake and the trasmission to go from 6 to 2 instead of 6 to 4. This is how my exhaust brakes worked in the past, but I don't if this applies to Jake Brakes.

John

John,

The Jake is independent of the tranmission and is integral with the engine. It functions by dumping compressed air from the cylinders when the coach is coasting. It has a high and low position which uses more or less cylinders.

A retarder is integral to the transmission, and when in use it will downshift as programmed. When using a Jake the driver must manually downshift.

Mango: FYI, Frank K., Jr. at Liberty was asked by A1 - why the retardo? vs the Jake? Response was - it stops better. End of discussion.

In addition the new lower sulphur fuel at 15 ppm has less BTUs, requiring more fuel to achieve the same power meaning that Al Gore has come up with a plan to burn more fuel to burn less sulfur? It is pretty well a given that the fuel economy of the series 60 will be negatively impacted by two tenths to .25 mpg with the new fuel. This according the Detroit Diesel representatives at the recent Liberty Rally.

Dang its cold - I liked the good old days before global warming, I hope it warms up soon.:cool: .

Fast Roger is an optimist.

Since I record every single gallon of fuel that flows through my bus I will be able to compare the last 12 months fuel burn per mile with the previous 12 month period and I will share the results at POG III.

I can't go further back because we got the Hummer 24 months ago and the Jeep was lighter.

I drive at the same speed so the results will show the real impact of the fuel change. It is probably double what DD says.

Quote:

---

Originally Posted by Gary & Peggy Stevens

Hey Mike, I think you can have a Retarder added to your new H baby, if you really wanted to? Somebody feel free to correct me if I am wrong about this.

Gary S

---

Gary,

Not at a good use of Lew Bucks at this time. I'll just learn to live with it and stop whinning.

Thanks

Mike

I have a question about our trans, kinda unrelated but.

Our trans selector has 5 marked forward gears yet I can feel, without a doubt, 5 distinct shifts giving it 6 forward speeds. Would someone care to shed a little light.

Also while at TGO talking with Bill he mentioned that he cruises at 50something and I asked him if that speed kept him from high gear because our bus won't even shift into final gear till 60 minimum. His responce was no, it is in final gear at 50something?

One more note for anyone trying to answer. There is a wide range from 1st to 2nd and 5th to 6th but 3rd and 4th have short close ratios. Also the build sheet shows the rear end has a 3.32 ratio, or is it 3.23.

Its an older bus and really can't say if its the original trans or not. Are there defining visual charicteristics between the 2?

The first "shift" you feel in your tranmission is actually the torque converter lock-up.

That would explain the firmness of it as well, downshifting too. Thank you Jon.

Quote:

---

The first "shift" you feel in your tranmission is actually the torque converter lock-up.

---

Thanks for explaining that. I've had exactly the same "feeling" on mine, i.e. one more shift than expected gears!

Regarding the shifts of the transmissions, and Jon is probably more up to speed than I am, I believe there are several gears where you go from converter to lockup. On the 6 speed the final 2 gears are really overdrives and I believe you are in lockup.

Jon, I also stopped at DDA today because I was curious about the manual down shifting when using the Jake Brake. The tech told me this can happen either manually or elctronically. In my case since I go from 6 to 4 immediately and automatically, it can be reprogrammed to go down thru the gears automatically and end at 2.

John

I know the retarder downshifts can be programmed with the normal downshift from 6th on the World transmission being to 4th.

I think if the Jake activation triggers a downshift it must be on newer coaches with the 6 speed transmission because on my 5 speed transmission (which had DDEC and ATEC) all downshifts were manual.

Gentelmen, I am back on for more information about my Jake Brake.

As I posted when I got my bus, back in March 08, I don't think my Jake Brake is SET properly? Can the Jake brake capability be adjusted somehow? I would like to have more braking power coming from the Jake when I release the accelerator.

Someone told me it should downshift the transmission, automatically if it is set up correctly, is this true? It seems to me, it has no way to do anything with the tranny.

I was told it could be adjusted or checked for proper adjustment? Anybody know if this is true, and which one of the many mfgs. is responsible for this.

Can it be looked at and adjusted by Prevost while in their shop?

Thanks

Gary S.

I think that a Detroit Diesel and Allison shop can help you with the Jake and downshifting which it should do.Back to the earlier post in this thread,I have a retarder and my new coach has a huge trans.cooler and I haven't seen the fluid temps.rise more than 8 degrees even in the mountains of NC,VA,KY(not real mountains)Black mountain on I 40 in NC is the greatest grade that I have descended with this bus and the temps are very steady all the way down.

My coach does not downshift when the jake comes on. I would not want it to downshift as I rarely turn the jake off. The jake works best with high engine RPM. As a rule I downshift at about 1400 rpm when slowing down for traffic lights, freeway exits and such. This requires less braking plus saving the brakes for a need to stop in a hurry when the XXXX pulls out in front of you.

I agree with Larry, I also know that they can be checked for adjustment and if they are out, when put back to proper specs will work better.

You want the downshift, that's where your going to get the most bang for the buck by high rpm's. If you have one that doesn't downshift to 4th gear (depending on speed) someone has had the program changed.

Truk,

I'm not so sure. My Jake on the first coach required a manual downshift and in retrospect I prefer that. At highway speeds my RPM would be more than adquate for most downhill driving. If I knew the grade was steep I then had the option of slowing down a little and dropping to a lower gear.

The retarder on the current coach automatically downshifts so I find myself leaving the switch on so I have retarder when braking, but I manually pull the little lever into the #1 or #2 position if I want the retarder to come on when coasting, like going downhill or approaching an exit. Otherwise I leave it off.

What I don't like about it downshifting automatically is if I am on cruise control, every time the cruise closes the throttle the brain thinks the retarder needs to come on so it downshifts, and then when the highway levels or goes up a little the transmission hangs in the lower gear for longer than I want it to. Up, down, up, down. It's like it is hunting.

My jake would not operate with the cruise on on the old coach.

Thanks guys for the replys. From what I am hearing I believe that my jake braking operation was changed. It works with the cruise on, which I want, and I can feel it work but only a little currently so I will have someone get in and check the set up of this system and evaluate.

To have it serviced at DD or Alison what exactly are they servicing? The DDEC IV computer or something else. In other words is it a computer controlled issue or mechanincal adjustment?

Thanks Again.

Gary S.

Gary, an Allison dealer can set & verify the transmission parameters via a lap top. You can have the transmission programed to try to down shift to a specific gear when the throttle is released & the Jake is on. Typically, you will see them set to try to get to 4TH gear. There are also solenoids in the valve train of the engine that can fail, or not fully engage. These can be checked by a Detroit shop.

When I was in FL picking up my bus, the technician mentioned that you can have the jake brake setup for "aggressive" mode. I don't know if this is fact or not, but I wouldn't be surprised, since as Steve indicated they are programmable.

My new coach, and as I remember none of my previous coaches automatically downshifted. I have to manually downshift in areas where I want more braking.

Ray

Awhile back I was stopped at a traffic signal. Yes it was red and had been for many seconds. Just before the signal turned green, I feel a thump on the rear bumper of my 1996 Lincoln Town Car. Now this is the third time I have been rear ended. I did not know my rear end was so very attractive!

Anyway, I get out and approach the offending vehicle. It is being driven by a little old lady, not from Pasadena, but a retiree from Whispering Pines. She causually rolled down her window and proceeded to say, " But I was slowing down." I could not help myself. I told her that was fine but my rear bumper was NOT part of her vehicle's braking system.

Life goes on.

Later ...

After having had a transmission retarder on our previous coaches that worked flawlessly, I was not to happy when my wife picked our current coach which has a 2 stage engine brake. After being told by Prevost I could have a transmission retarder added for approx. $ 20k, I decided to proceed, the price tripled; then they concluded it couldn't be done because of cooling consideration. My son suggested I go to Penn Detroit Diesel in Ocala. I bet the tech a lunch he could not improve the stopping characteristics to match a transmission retarder. Happily I lost the bet!! It took 18 minutes after he hooked up his laptop...he let me modify the transmission profile. He explained to me that they reprofile many entertainer & converter coaches from activate on 6th gear only to as many gears the driver prefers. When I took the coach back to Marathon (FL). The techs (several of whom had brought the coach to NC) drove the coach and were amazed at the difference in how the coach stopped.

Reposted for revelancy.