View Full Version : Exhaust Brake & Transmission

06-09-2008, 09:04 PM
Coincidence or not??... Has anyone had a any experience with exhaust brake causing problems with performance or damage to engine or transmission???

Last week I installed a BD exhaust brake in my 2006 F250 with tow/haul. Took off next day with BH bound for Texas Speedway to take in Indy cars and continue with trip to Calif and back to Texas. No real necessity for exhaust rake on the road at this point... just checking it out. Well, while running both tow/haul and exhaust brake engaged and about 100 miles into trip noticed tow/haul flashing and transmission gauge registering "cold" (needle at bottom of gauge). About this time lost power and reduced to about 5MPH . Fortunately, saw a Ford dealer about one block ahead and pulled in.

Bottom line the transmission "valvebody-solenoid body" was replaced. Repair was covered by warranty. Hopefully the problem with the transmission was purely a coincidence and not related to the use of the exhaust or installation.

Have not had any previous experience with driving with an exhaust brake and would appreciate any tips.

Thanks, Jerry

06-09-2008, 09:14 PM
Sounds like your valvebody was ready to go and you just gave it the push it needed with the exhaust brake.

06-09-2008, 09:21 PM
If there was any possible way that exhaust brake caused the tranny to go out, you bet that Ford would't cover it under warrenty as it is an aftermarket item. Most manufacturers will not cover an item that fails because of an aftermarket item that is installed. That's been my experience and the experience of numerous people that have had that happen.

06-09-2008, 10:58 PM
Wonder if my 2007 Ford F550 has a similar issue happening? I had ascended and descended the hills from St. Louis into Branson with great ease, towing the trailer. But on one of the last hills, while ascending, the truck went from 55 MPH in Tow/Haul mode with Cruise Control on, the truck lost nearly all power. It felt as though the cruise control had shut off. But that was not the case.

I "limped" up that hill at maybe 25 MPH. Then on the next hill, still in Tow/Haul mode but no more Cruise Control, I was still power starved. The next hill, I purposely gained enough momentum going down it to sling myself up the other side. Then we got off the highway and into town to the KOA.

The truck has been fine in town. I have not seen my unit weights yet. Should get my report from Weigh-It tomorrow (Tuesday). But I don't think it's the weight that it the issue.

If the truck acts up on the way home next Sunday, I will have to take it into Ford I guess.




Forrest Fetherolf
06-09-2008, 11:35 PM
Jim B.

Buy a code reader with erase.


I have this one, you can read the trouble codes, erase the code, and turn off check engine light. Once code is erased, the check engine light will turn off and limp mode will be canceled.

I used mine twice when the above occurred due a plugged fuel filter.


06-10-2008, 10:48 AM
I don't believe the "check engine" indicator came on during this event. Although the "tow/haul" was flashing off and on. I had read the owners manual, but did not recall that the flashing "tow/haul" is an indicator that something is wrong and needs immediate attention!!

I hope the observations that the event is coincidental with the installation and use of the exhaust brake are correct.:o

Anyone have experience with exhaust brake use in the "tow/haul" mode on the Ford F250 diesel? Do you engage just the exhaust brake or both together?

Thanks for the comments.None

06-10-2008, 07:44 PM
I don't have a Ford but a Dodge and I run my BD most of the time when I'm in hills etc. I do override and run Tow/Haul if I feel the need. My Tow/Loc which was installed along with the brake to save the tranny auto downshifts to Tow/Haul at 50 MPH if I'm in overdrive. The fellows who installed the brake say to leave it on all the time. By the way, Chrysler have put a "restriction" on my drive train because of the brake. I have not experienced any signs similar to yours, again I have a Dodge.../Doug

06-10-2008, 08:09 PM
I assume that the "restriction" was a formal notice of some sort. I installed mine myself... I understood Tech support to say that both tow/haul and exhaust brake can be active at the same time. Do you activate the exhaust brake alone, and then it activates tow/haul itself, or do you manually select and activate both yourself and then proceed to tow in that mode?

06-10-2008, 10:19 PM
When you run the exhaust brake, the torque converter clutch should be locked up. If not you could overheat the transmission, and that could put the truck into limp mode.

If you have a tranny gauge you could watch that easily enough. Not sure about the Fords, but on our Dodge we had to add a controller to make sure the clutch was locked up, when using the e-brake. Otherwise when you turn on the e-brake you are just slipping the converter backwards, creating a tremendous amount of heat from fluid friction.

06-10-2008, 10:48 PM
Thanks Forrest. Another rally attendee has a code reader and will see what we can see tomorrow. Spoke to Ford today and their guess is that it was an EGR valve stuck open. Truck runs fine now and I ran it hard today on the highway (not towing) and it ran great. I do plan to get a ScanGaugeII (http://www.scangauge.com/products/) at some point and I will pickup a fuel filter replacement kit and carry it and the tools with me to change on the road if ever needed.


Terry H
06-11-2008, 12:23 AM

I have a Code reader called Scan Tool that connects to a Laptop by a USB cable and a DTC adapter. I can show it to you, demo or read and clear code from your truck. For more info go to: http://www.autoenginuity.com/products.html

06-11-2008, 07:01 PM
ok guys i am not mechanical. What is a brake exhaust and do I need one, since my Ford has only 5,000 miles on it and what is the benefit? Or is there factory brake exhaust on my truck already? All I can tell you is I get 9-12mpg while towing.

06-11-2008, 08:07 PM
Hey Lar, you should get an exhaust brake cause it help reduce green house emissions. Breaks the exhaust in little bitty pieces. BTW, the tow/haul in the transmission does about the same thing. SO, NOW YOU ARE TROLLING FOR SOMEONE ELSE TO HELP YOU,HUH!!!!! OK, THE JIG IS UP, IM BRINGING MY SAWZALL TO PUT IN THE WINDOW. All we need to do is drill a BIG hole in the wall,stick the saw blade through the hole and cut out around the window. Super glue and duct tape will make it good as new. LOVE YA BOB:D:D:eek: P.S. XM is just as good as sirius

06-11-2008, 08:10 PM
For a long time, exhaust brakes were taboo on the 6.0 because of the variable geometry turbo functioning as an exhaust brake itself in tow/haul mode. I see now they have the stuff figured out to keep the turbo from overboosting when the brake is used in tandem.

Jim, your problem could be what they call lot-rot. The VGT is very susceptible to rust on the vanes and plate, which make the vanes stick one way and overboost, or stick the other way and make no boost. It's a good idea to run the truck at least once a week, and run it hard. If the EGR was stuck, it would throw a code and light the SES light too. The stuck turbo would throw a code as well. The fix for lot-rot is to remove the turbo and clean the rust and crud off the turbo guts.

You can check your EGR yourself on a 6.0. It sits right on top of the engine, right behind the intake elbow. It's a silver can with a wire harness coming right out of the top of it. You remove 2 bolts(i think they're 10mm heads) and give the body a twist. There is a plate that the two bolts go through that you can now take a metal hanger and loop the ends through the slots. Take a mat or pad, lay it on top of the alternator. Use a heavy dowel or pipe to leverage the EGR out of the intake. It is stiff, there's two rubber o-rings that want to keep it in the intake. Take off the o-rings, and the fiber gasket before you hose it down with carb cleaner. When you're done cleaning the sludge off, make sure that the valve heads can seat down properly in the body. Slide the fiber gasket on, then the two o-rings. Apply a light coat of anti-seize on the o-rings and slide the EGR back into the intake. Do your best to seat the EGR by hand, and try not to use the two bolts to draw it down. Plug it back in and you're done.

There is a DIY process to take care of the lot-rot, but it's MUCH more involved than the EGR.

Larry, I would think that the brake on a 6.4 may be a little while coming yet, with the sequential turbos on the 6.4 doubling the work. It's a butterfly valve that slows the flow of exhaust gas heading out of the engine to create some extra backpressure on the engine to force it to slow down the truck like a gas engine does when you let off the go pedal.

06-11-2008, 09:20 PM
I have a Banks exhaust brake. I don't have the tow haul transmission but do have the trans-command module from Banks. I have to manually turn a switch to engage my exhaust brake. When it is engaged it will slow the truck until it gets to about 1200 rpm then will disengage. Not long ago the exhaust brake stuck closed and when I tried to accelerate I had no power. There was much black smoke from the exhaust pipe. The exhaust brake closes a valve in the exhaust manifold and if it sticks closed then exhaust pressure kills the engine power. Your problem sounds like the one I had with the exhaust brake valve sticking closed. What I did to clear mine was stop the engine, wait about 2 minutes and then start back up with the exhaust brake turned off. Now I only turn on the exhaust brake when I need to use it and it has been working okay. When I don't need it I turn it off.

Your might check with BD technical and get their advise.

06-11-2008, 10:07 PM

Thanks for the DIY teardown :) Not sure I am up for that. But you could be right. Truck was built 10/2006. Truck sat until 8/2007 and was upfit and delivered in 10/2007. So a year of sitting on a lot. Lots of external rust on suspension etc.

And then it sat all winter long - being started maybe once every 3 weeks.


06-16-2008, 04:18 PM
I have a BD exhaust in 05 Dodge with 48re Transmission. The diesel shop that installed it say not a problem to run even when not towing. When towing I use Tow haul mode all the time with trailer and BD brake. Works great. When not towing and not in a city I use Exhaust Brake all the time. It saves the original brakes.

08-11-2008, 09:01 PM
I'll admit I'm new to this game, but I want to learn as much as possible. So what is "tow/haul"? Is that a button that will be on my 06 Ford F250?( I just bought it and will pick up this week.


08-11-2008, 09:46 PM
On a Ford Torque-shift the tow haul button changes the shift points in the transmission to a higher RPM on the upshift.on a downhill a tap of the brake will downshift one gear at a time as long as the speed will not over- rev the motor. It kind of acts as an exhaust brake.I hope that helps you understand.Jon.:)

08-12-2008, 05:21 AM
This tow/haul switch is a push button switch, located in the end of the gear shift lever and is a great brake saver.

08-21-2008, 03:51 PM
Reading all this technical stuff got my head spinning....