Diesel Engine Brakes

[Stomper]

Is that how you keep your ankles so nice all these years? Let the engine do the braking for ya?

Actually, word from the prison yards is that @Certaindeaf has callouses on his ankles…..

 

[TTSX]

Hence the entire reason for this thread, I'm certified to do brake work but transmissions are something I only have experience sweeping floors around, at least when I turned 16.

You don't need to be certified to do brake work.

Transmissions aren't nearly the black magic people think they're are.

Bottom line is, it just isn't worth worrying about.

 

[kmk1012]

You don't need to be certified to do brake work.

Transmissions aren't nearly the black magic people think they're are.

Bottom line is, it just isn't worth worrying about.

I agree but to work for certain large companies, certifications are required to keep insurance rates, as well as comebacks at a lower rate. LS really doesn't want brake complaints because that is one of their biggest profit margins. As far as transmissions, my 14 year old son and I almos completely disassembled my 16 year old daughters Jeep trans to fix an internal issue a few weeks back. I figured, I'll risk $300 to fix a brakes tranny and if it doesn't work, it's still less than 10% of the quoted repairs. It worked like a champ, I'm glad to be YouTube Certified!

 

[Provincial]

I rebuilt the 4R100 in my F250. I had to make some of the tools, and improvise others. I bought an aftermarket (ATSG) manual that was very understandable and comprehensive, and I did research on upgrades to make the transmission more durable and longer lived.

Having a decent size, durable work surface is key. I have a 4x6 foot table made of 3/4" steel plate that is sanded smooth on top. Clean the surface and all the parts and avoid dust and lint. Cover the area when not working and do not expose it to airborne dust or other contaminants. Keep your tools and everything than will come in contact with the transmission or the parts clean. Cleanliness is the key!

 

[Nwcid]

Did you add an exhaust brake (I.e. Jake Brake) to your 2016 Duramax? If an exhaust brake wasn't added then I believe you are just using engine braking which is different.

I think you have your terms backward.

Yes, Jake brake, ie engine braking is different than exhaust braking.
A "Jack Brake", invented by Jacobs Vehicle Systems in the mid 60's is an engine brake and found on heavy duty trucks like my Volvo.

Modern light duty trucks like my Chevy 1 ton dually come with exhaust brakes.

No, I did not add an exhaust brake and no, the Duramax does not have an engine brake. "Engine – Duramax® 6.6L V8 Turbo Diesel; Horsepower: 397 @ 3000 rpm: Torque: 765 lb.-ft. @ 1600 rpm. Includes exhaust brake, dual 730 CCA, 70 amp-hr. batteries and engine block heater. Requires Allison® 6-speed automatic transmission."

 

[The Heretic]

You don't need to be certified to do brake work.

Transmissions aren't nearly the black magic people think they're are.

Bottom line is, it just isn't worth worrying about.

I've done both, including and up to a 21 speed John Deere tractor transmission that is manually hydraulically shifted trans with multiple clutch packs and valve body (no torque converter) and hydrostatic drives (swivel plate). For a number of years, that is what I did as a profession.

Yes, transmissions and differentials are not magic of any kind, but they are beyond the ken of most backyard shadetree mechs, while most brake jobs are easily taught and done by same. I don't do my own transmission work anymore - I pay to have it done. I am too old, decrepit and lazy to do it, and I don't have a lift or the jacks/etc. to pull/drop a transmission that weighs 200# (not including the transfer case). Paying someone is not cheap - just having the filter and fluid changed on my BMW costs $1K.

But doing the brakes on my truck is something I can still do without a heart attack and with the tools I have on hand.

 

[The Heretic]

Really, unless you have something slamming, compression braking is the same as coasting in gear with a standard transmission. The gear teeth are contacting on the opposite side from the side under power, so no additional wear going forward. Same for any splines or U-joints, and the clutches are locked up anyway.

Yes - but I have slop in my drivetrain and fifth gear is gone too. I don't know how the PO(s) drove the truck, but there is a lot of give somewhere (probably not the trans, probably the u-joints and/or the rear diff). It makes a difference - even if it is just the diff, a diff properly replaced and/or setup with the correct alignment/backlash/etc. of pinion/ring gear is not something a backyard shadetree mech is experienced with and usually doesn't have the proper tools for (most don't have a dial gauge or the experience to use one).

Also, diff ring gears are not designed for compression braking or pulling/climbing something in reverse - they expect the load while going forward. So the wear/load on the ring gear is not the best. Not saying it will break the gears, but high loads on the backside of the gear tooth are not good for it.

I am going to get diff lockers for both my truck and pickup, so I am not bothering with looking into it right now (beyond playing with the driveshaft - which I have done and I am pretty sure it isn't the u-joints). I've got a lot of work to do on my truck before I use it anywhere more than a few miles from my house; brakes, front end, trans, etc. all need some major overhaul - but I mostly use it to haul firewood from my back acreage for now.

 

[Nosferatu]

I wouldn't worry about it. I fix this crap for a living and can't say I've seen too many power train failures from engine braking.

Come fix my F&#C@&*N F350!

 

[Provincial]

Come fix my F&#C@&*N F350!

What year, engine, and transmission?

 

[Nosferatu]

What year, engine, and transmission?

2013 6.7, 6-speed

 

[Provincial]

Too new for my experience. What is it doing wrong, or not doing?

 

[Nosferatu]

Too new for my experience. What is it doing wrong, or not doing?

No crank. I threw a new starter and ignition switch at it - cause they're cheap and quick - to no avail. Checked all fuses and tested relays. Getting a "Starting System Fault" on the screen, but no ODB codes stored. Batteries are new as of last Summer and both check out good with my tester. I keep it on a battery tender.

Local shop is 2+ weeks out, so just waiting on a call from them when they're ready so I can tow it in and have the pleasure of likely spending a few grand on it...again.

 

[The Heretic]

No crank. I threw a new starter and ignition switch at it - cause they're cheap and quick - to no avail. Checked all fuses and tested relays. Getting a "Starting System Fault" on the screen, but no ODB codes stored. Batteries are new as of last Summer and both check out good with my tester. I keep it on a battery tender.

Local shop is 2+ weeks out, so just waiting on a call from them when they're ready so I can tow it in and have the pleasure of likely spending a few grand on it...again.

I really like my 2014 BMW - but although it has never had any serious malfunctions, I will not rely on it as a SHTF vehicle. My '97 Dodge will always start (as long as I keep the batteries charged) and run.

 

[Unka-Boo]

I think you have your terms backward.

Yes, Jake brake, ie engine braking is different than exhaust braking.
A "Jack Brake", invented by Jacobs Vehicle Systems in the mid 60's is an engine brake and found on heavy duty trucks like my Volvo.

Modern light duty trucks like my Chevy 1 ton dually come with exhaust brakes.

No, I did not add an exhaust brake and no, the Duramax does not have an engine brake. "Engine – Duramax® 6.6L V8 Turbo Diesel; Horsepower: 397 @ 3000 rpm: Torque: 765 lb.-ft. @ 1600 rpm. Includes exhaust brake, dual 730 CCA, 70 amp-hr. batteries and engine block heater. Requires Allison® 6-speed automatic transmission."

If it's like medium duty trucks, they do it with closing the vanes on the turbo and trans settings ( lockup/gear selection )

 

[Unka-Boo]

No crank. I threw a new starter and ignition switch at it - cause they're cheap and quick - to no avail. Checked all fuses and tested relays. Getting a "Starting System Fault" on the screen, but no ODB codes stored. Batteries are new as of last Summer and both check out good with my tester. I keep it on a battery tender.

Local shop is 2+ weeks out, so just waiting on a call from them when they're ready so I can tow it in and have the pleasure of likely spending a few grand on it...again.

Neutral safety?

 

[Nosferatu]

Neutral safety?

I thought about that - and is a likely culprit, but I'd have to drop the transmission oil pan to get to it and I don't like opening up the tranny on a dusty gravel driveway.

Plus I'm sick and tired of crawling under vehicles on this stupid gravel driveway as well - getting too old for that bubblegum!

 

[Nosferatu]

I really like my 2014 BMW - but although it has never had any serious malfunctions, I will not rely on it as a SHTF vehicle. My '97 Dodge will always start (as long as I keep the batteries charged) and run.

I'm not worried about SHTF or anything, this is my hauler. It drags my dump trailer with the tractor and excavator to and from MT, as well as my travel trailer when camping with the spousal unit and my hunting/fishing truck camper when it's just the dog and I and gets building materials around. It's been *mostly* reliable in it's 165k miles. I had to replace the exhaust manifolds and turbo a couple years ago and a few minor things here and there. I'm working from home now and have the Bronco for errands, so it's not getting the commuter miles anymore. Hopefully it will hold up longer.

 

[Ura-Ki]

SO, there are Three kinds of "Diesel Brakes" and the vast majority of your pickups use only ONE!
Jake Brakes ( an Actual Exhaust Brake BTW) , that's ONLY found on the large diesel engines, usually 10L and up ( Yea, some small DDEC's have Um) so don't worry about those, these are the only mechanical Exhaust Brake out there, a Clessy Cummins Invention, he failed to patent and Detroit Diesel jumped on it and filed the patent and called it,.....................The JAKE BRAKE!
Down Tube Brakes, ( Cummins Patent PAC-Brake, Often incorrectly called "Exhaust Brakes") this is by far and away the most common "Brake" system your going to find on small diesel engines, it's literally an exhaust throttle, in that it closes off the exhaust after the turbo to provide the back pressure that gas engines are known for, that nice hold back your used to.
Magneto Brakes ( Called Brake Savers), this has been around for over 50 years, on some engines it works, some they haven't figured them out, the big users are CAT and Volvo, and some of the older Cummins KT series Engines especially the Big KTA-440 and even bigger KTA-600 engines, it's literally an electro magnetic flywheel brake, and when it works, it REALLY works. My Big CAT 3408 has BOTH the Brake Saver and a full rack of JAKE'S and you can only run One system unless there is a big load behind it, otherwise things down stream get REAL EXPENSIVE!

So, your Pickup uses a Down Tube Throttle, that's it, and there is Almost no issue with running around with it "ON" other then some temperature issues you should watch for, but there is NO mechanical load on the engine it's self, only the valve and it's moving parts and controls, So run it how ever you wish, there is NO disadvantage to running it constantly, it only works when you let off the throttle and once the RPM's drop to near idle, the valve opens and the engine continues to run as normal!
The Biggest issues these systems have is the valves locking up, ether because of too much heat, or loss of lubrication in the oil-lite bushings, and the seals tend to fail over time, with Cummins, it's an easy repair, and the valves are cheap enough to replace, ford and GM, not so much, but still almost reasonable, even Isuzu runs this system, and are one of the best there is, for engines that don't have one, use the Isuzu valve, you'll thank me later!

 

[Unka-Boo]

I didnt wanna type all that in my phone

 

[Unka-Boo]

I thought about that - and is a likely culprit, but I'd have to drop the transmission oil pan to get to it and I don't like opening up the tranny on a dusty gravel driveway.

Plus I'm sick and tired of crawling under vehicles on this stupid gravel driveway as well - getting too old for that bubblegum!

If you can find a wiring diagram, you can jump the circuit and see if it's the culprit