Exhaust Brake Unavailable

[EZeis]

Earl,

TH has second order effect on EB... EB functions on RPMs... TH has longer shifts up and faster shifts down that raises RPMs, hence the better performance on the EB. You can do the same thing TH off, you manually downshift, and take you foot off the accelerator in EB normal mode. Does that make sense?

Hope this helps.

Cheers, Ron

I understand how it works. Lol I even explained it in previous posts. Just arguing that the braking is much better in TH mode where some have said it's not the case. What do ya do? That guy has changed his tune, so maybe the circle will go sqaure.

Not so sure the torque converter will lock the same using manual downshifting vs TH. I never used it that way. I use it to lock out gears to prevent hunting. Also if I'm in a hilly curvy area I will drop a a gear or tow or three to keep the power performance up.

Earl

 

[EZeis]

Exhaust braking works the same amount with or without the tow/haul engaged, no difference in strength. What the tow/haul does to help with the EB process is continue to downshift as the truck slows to keep the EB in a working RPM range, where if it is off the truck will not downshift as the truck slows, it slows down as much as whatever gear it's in allows, then the converter unlocks when RPM drops below 1100 and it no longer has EB applied.

Yep, even mentioned that. But simply said, braking performance increases with TH on. I'm not arguing the details. The details is just that, details. When someone tells me TH doesn't change the braking performance, I call them out on it.

Earl

 

[EZeis]

What I said is that TH has no bearing on EB function. The benefit, as stated, is from the transmission. The brake itself works the same.

I never said you don’t slow down faster in TH/EB.

You weren’t following and assumed I had an issue, when I don’t.

You also stated it wasn’t worthwhile to use your EB when not in TH. That itself is wrong on a properly working truck.

If you haven’t don’t it yet go back and re-read what has been stated.

All good, I just took this as you agree the braking performance is different between TH disabled and enabled. See how simple, simple is. I'm surprised you didn't build me a logic ladder of the programing to demonstrate. Not sure why you were arguing if we were on the same page?

Not budging off on the braking performance is too weak for me to use without TH enabled statement. Just is. Don't know what to tell you. Coming from a pacbrake prxb, I have higher expections of exhaust braking. Hell my wife knows right away when I forget to turn on the EB or forget the TH enabled and she knows nothing about vehicles nor has driven my truck and can tell the difference from the passenger seat.

Note, quite a few of us run TH enable strictly for the improved braking performance.

Note, some ppl won't run TH empty cause it's too aggressive for them. That in itself should tell you there is a improvement. Night and day on my Aisin 3.42 truck.

If I couldn't run TH, I'd have to look into aftermarket exhaust/engine braking as I wouldn't care for the braking performance otherwise.

Earl

 

[Wiredawg]

I understand how it works. Lol I even explained it in previous posts. Just arguing that the braking is much better in TH mode where some have said it's not the case. What do ya do? That guy has changed his tune, so maybe the circle will go sqaure.

Not so sure the torque converter will lock the same using manual downshifting vs TH. I never used it that way. I use it to lock out gears to prevent hunting. Also if I'm in a hilly curvy area I will drop a a gear or tow or three to keep the power performance up.

Earl

Earl,

EB is more aggressive in TH, so it could be said it is more effective. I see your.point. It doesn't really matter if it's first order or second order, it just is thanks to trans shifting differently. I guess all could agree EB is MOST effective when used with TH.

Thanks for seeing the same thing in a different light.

Cheers, Ron

 

[EZeis]

Earl,

EB is more aggressive in TH, so it could be said it is more effective. I see your.point. It doesn't really matter if it's first order or second order, it just is thanks to trans shifting differently. I guess all could agree EB is MOST effective when used with TH.

Thanks for seeing the same thing in a different light.

Cheers, Ron

Keeping stuff simple is, well, simple. Exhaust braking have more performance with TH enabled? Yep, that's a fact and I can prove it. Don't care if it's unicorn poop that causes it when you push the EH button. Sometimes some ppl get so involved in the details they can't agree on something so simple.

Braking performance significantly increased with TH enabled? Yep, I can prove that as can anyone on their own.

Braking performance much weaker with the TH disabled? Yep, I can prove that as can anyone on their own.

Earl

 

[p-Bar]

Earl I agree with you. I use mine all the time and will use it in the tow haul mode. Exhaust braking is more pronounced because the engine is using higher RPM's in T/H mode than non T/H mode.

 

[Cummins12V98]

You get higher braking power with RPM and load, that's where the tow/haul comes in, by downshifting the trans, the RPM and loading stays higher, but RPM for RPM the braking power is the same whether tow/haul is on or not.

I will report what I find.

 

[Cummins12V98]

Yep, even mentioned that. But simply said, braking performance increases with TH on. I'm not arguing the details. The details is just that, details. When someone tells me TH doesn't change the braking performance, I call them out on it.

Earl

Concur

 

[Cummins12V98]

Keeping stuff simple is, well, simple. Exhaust braking have more performance with TH enabled? Yep, that's a fact and I can prove it. Don't care if it's unicorn poop that causes it when you push the EH button. Sometimes some ppl get so involved in the details they can't agree on something so simple.

Braking performance significantly increased with TH enabled? Yep, I can prove that as can anyone on their own.

Braking performance much weaker with the TH disabled? Yep, I can prove that as can anyone on their own.

Earl

Concur

 

[Ozymandias]

Will this thread ever end turning in circles?

 

[EZeis]

Will this thread ever end turning in circles?

I think it's going square but time will tell if it stays in a circle.

Earl

 

[Ozymandias]

 

[AH64ID]

Keeping stuff simple is, well, simple. Exhaust braking have more performance with TH enabled? Yep, that's a fact and I can prove it. Don't care if it's unicorn poop that causes it when you push the EH button. Sometimes some ppl get so involved in the details they can't agree on something so simple.

Braking performance significantly increased with TH enabled? Yep, I can prove that as can anyone on their own.

Braking performance much weaker with the TH disabled? Yep, I can prove that as can anyone on their own.

Earl

Then prove it. I will prove that you can get the exact same retarding hp without using TH. It’s that simple. It’s not complex to understand how the two work in conjunction with each other, but still have 100% independent programming and method.

The simple answer is that TH makes the EB more effective under many circumstances, but does nothing to make it stronger. That’s the difference in what we’re saying.

But it’s all I’m fun.

I prefer wavy to circle or square.

 

[Cummins12V98]

Will this thread ever end turning in circles?

I’m dizzy

 

[Wiredawg]

TH makes optimizing the EB EASIER than doing manual downshifting of the trans, but it can be done. I'm OK with others not caring about the how to's not being important, but for me, I like to know how stuff works, relationships, and interelationships.

I guess at this juncture, it"s time for me to jump off the merry go round and let it go... Can't address unicorn poop. ugh.

Cheers for the remaining partakers in this discussion. Ron Out.

 

[kthaxton]

Admittedly I've skimmed the last page and a half so I may have missed someone mentioning it.....but it seems many people are missing the most important factor in why EB works better in low gears.....while cylinder pressure may have some influence....the biggest influence is the lower gears themselves.

Lower gears basically give the engine more influence or control of the vehicles movement, whether accelerating or decelerating. When in a lower gear, it's easier for the engine to slow the load be it via EB on a Diesel or restricting air on a gas engine. It's all because of gear reduction.

Find some sort of contraption with shiftable gears (like manual trans on a bench or small light vehicle of some kind like a motorcycle or ATV maybe), try pushing it or spinning the output shaft in a high gear, then try it in a low gear. You will find it is a lot more difficult to push/spin it in a low gear.

 

[SnoKing]

Will this thread ever end turning in circles?

It is about as bad as threads on RV.net get ALL THE TIME. Just use the EB the way you wait to. For me it was more of a driver involved situation. I ran Full Exhaust brake and when towing the 16K 5th wheel at a combined 24,500 lbs I manually selected the gear I wanted to be in descending a pass or mountain and regulated when the EB was on or off with the throttle pedal. It worked for me and I felt in control. Times I tried the EB in auto mode I never felt in control. I guest some of this was coming for the 2001.5 with Banks EB and the DTT built 47RE with Bill's smart controller towing at 21K combined. It took driver involvement to make that work and we made many West Coast annual commutes between Washington and Arizona. Empty the 2001.5 would chirp the tires on a lock to lock down shift. I would add that I never put new pads on the 2001.5 or the 2015 for wearing them out.

Now the rig in the top line of my signature is going to be a different animal as it just seems to free wheel when you let up on the throttle. To use engine braking I am going to have to learn up on the Sport mode and paddle shifting. Only drove in last summer for a couple months and a few weeks here in Az. Son and his FIL drove it down here for us. It is fun, a 4500 lb SUV that will do 0-60 in 5.7 seconds, 14.1 quarter miles at 98 mph.


It's time!

 

[Jim W]

Just purchased the truck in Fall and haven't driven it on the salt laden winter roads in NE Ohio. Took it for a 300 mile drive and it ran just fine. No codes displayed that I'm aware of. Would they be displayed on the dash?

After Mark's questions, I think we all scared him off. He has not posted since Sunday after 11:00 AM. Did any one really answer his questions? I know I asked him a question but he never answered my question! So how can we really help if all of the facts are not presented!

 

[SnoKing]

Admittedly I've skimmed the last page and a half so I may have missed someone mentioning it.....but it seems many people are missing the most important factor in why EB works better in low gears.....while cylinder pressure may have some influence....the biggest influence is the lower gears themselves.

Lower gears basically give the engine more influence or control of the vehicles movement, whether accelerating or decelerating. When in a lower gear, it's easier for the engine to slow the load be it via EB on a Diesel or restricting air on a gas engine. It's all because of gear reduction.

Find some sort of contraption with shiftable gears (like manual trans on a bench or small light vehicle of some kind like a motorcycle or ATV maybe), try pushing it or spinning the output shaft in a high gear, then try it in a low gear. You will find it is a lot more difficult to push/spin it in a low gear.

So last year or maybe two years ago we had a similar discussion and I did high speeds exits off the 202 loop which is a down hill run to Elliot Road, with and without the exhaust brake and proved what you are saying is completely wrong. Without the EB and in TH the truck slowed very little and I even tried it forcing earlier down shifts. The Cummins just free wheels. The EB does the real work and being in the right gear for the speed keeps in working. Without it you better hit a green light at the bottom of the exit ramp so you can continue onto the entry ramp.

I would add that for some reason the V-8's, think Power Stroke and Duramax, when they had grade braking they did closer to what you are talking about. Those engines did much better regarding holding back. Not true on the I-6 Cummuns. Before I put the Banks EB on the 2001.5 I would trick it into keeping the torque converter locked with the cruse control and it only had a minor effect of hold back on hills. There is a nice LONG grade on I-84 coming down into Ellensburg, Wa where I would try that.

 

[kthaxton]

So last year or maybe two years ago we had a similar discussion and I did high speeds exits off the 202 loop which is a down hill run to Elliot Road, with and without the exhaust brake and proved what you are saying is completely wrong. Without the EB and in TH the truck slowed very little and I even tried it forcing earlier down shifts. The Cummins just free wheels. The EB does the real work and being in the right gear for the speed keeps in working. Without it you better hit a green light at the bottom of the exit ramp so you can continue onto the entry ramp.

I think you totally misread what I said. I did not discuss a scenario of NOT using the EB.

Simplified points of my post....
EB works better in lower gears, whether you manually shift down, or use T/H and it automatically shifts down.
EB works better in lower gears primarily from the gear reduction itself, not just engine RPM.