2blackdogs
Anywhere we stop but home is New Mexico
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On another topic that was recently posted I read that using the exhaust brake on long downhill decents will heat up the tranny fluid.
I was not aware of this. Is this correct and why would it heat up the tranny?
Bob
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Turbo Diesel Dude
Green Mountain, NC
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Joined: 01/10/2005
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I run with my exhaust brake on all the time on my '08 Dodge. Personally, I don't think it has any affect on the transmission as the engine is doing the work not the tranny.
charles weidman
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mowermech
Billings, MT
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Joined: 06/28/2003
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If there are any warnings to be considered, they will be in the Owner's Manual.
I'm with you, based on a long career as a mechanic, I don't see why there would be excessive tranny heating.
Now, if you had a "Hydraulic Retarder", YES that WILL cause fluid heating if overused. I don't know if anybody even makes them anymore. No great loss, if not.
If such use of an EB DOES actually cause auto tranny fluid heating, there's another reason to have the manual tranny!
CM1, USN (RET)
'94 Dodge 3500 4X2 CTD, 5 speed, 4.10 LS diff., Jacobs Rambrake, 274,000 Miles
'99 Monaco McKenzie 32' triple slide
'95 Tioga 29H Ford-based Class C
Daily driver: '08 Subaru Outback
Towed: '06 Jeep Rubicon Unlimited/Load Trail 16' flatbed
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Retired_nuke_ET
Carrollton Va.
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If the torque converter is not locked up the excessive slippage will heat the fluid. If I remember right, on Dodge an EB was not available on early models with an automatic until their programming was changed to lock up the torque converter when the EB was engaged. I believe most third party EB makers offer a control box that will force the tranny to lock up.
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coolbreeze01
Redding, Ca
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Joined: 08/24/2006
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2blackdogs wrote:On another topic that was recently posted I read that using the exhaust brake on long downhill decents will heat up the tranny fluid.
I was not aware of this. Is this correct and why would it heat up the tranny?
Bob
Some older automatics need a controller in conjunction with the exhaust brake to keep the transmission in lockup. Slippage will cause heat. In a correct installation, using the Exhaust Brake does not raise fluid heat on long downhill descents.
If you are interested in adding an EB to your truck, BD Performance or PacBrake will have what you need plus answers to all your questions.
2008 Dodge 3500 CTD LB SRW 4X4 6-Speed Auto
P3 Blue Ox Sway Pro
2007 Komfort 212
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targaboat
sulphur springs, tx, usa
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Yes, with the lockup you have the minimum transmission oil heating. However, even without LU on the heating will be far less than normal up hill driving. And the engine speed being up will ensure that the cooling systems are functioning. The reason for having the lockup on is to keep the engine speed up for without high engine speed the engine braking will not be effective. I just had to speak up for over 40 years of working with torque converters, I am frustrated with the large quantity of false information circulated on the forum.
Allison still builds a retarder which is a second TC which can be turned on for down hill travel. The entire quantity of heat is then tranfered into the the oil which has be removed by heat exchangers(radiators). These are very expensive and with the effective control systems available today in conjunction with the exhaust brakes and LUs, they are very seldom justified except on the very large and expensive over the road systems. A very few of the top of the line MH have them.
* This post was
edited 03/01/09 03:16pm by targaboat *
Fly Boy
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