exhaust brake ruin transmission

i have spent the last 2 days spec-ing trucks out, the one in question is a 2010 GMC k3500, with the duramax/allison transmission..... one thing that im wanting is an exhaust brake, but GM wont install/ doesnt install them on the duramax with the allison trans..... out of curiosity, i looked at the 2010 dodge cummins 3500 and it has an allison trans as well, but they install a exhaust brake factory, as standard equipment..... why is it that chevy wont???? i was told by someone that unless you lock the torque converter up, an exhaust brake will cause torque from the rear axle holding back, to overheat,and fry the transmission.... any insight???

exhaust brake?

1993GMCSierra wrote:

exhaust brake?

Yes, exhaust brake. Not to be confused with a jake brake.

http://www.dieselpowermag.com/tech/general/0712dp_2005_gmc_sierra_duramax/index.html

batty1214 wrote:

i have spent the last 2 days spec-ing trucks out, the one in question is a 2010 GMC k3500, with the duramax/allison transmission..... one thing that im wanting is an exhaust brake, but GM wont install/ doesnt install them on the duramax with the allison trans..... out of curiosity, i looked at the 2010 dodge cummins 3500 and it has an allison trans as well, but they install a exhaust brake factory, as standard equipment..... why is it that chevy wont???? i was told by someone that unless you lock the torque converter up, an exhaust brake will cause torque from the rear axle holding back, to overheat,and fry the transmission.... any insight???

I thought the Dodges came with Aisin transmissions? Last I heard only GM used the Allison. Anyway...

I have asked the same question and cant get a straight answer. As you've touched on, the problem is heat. Off throttle, an automatics line pressure decreases, causing the torque applied through the clutch packs to create more slippage and more heat. Fortunately, when in tow/haul mode, the Allison locks the converter and keeps the line pressure relatively linear so it doesnt have that problem. But I still dont know why you cant get an exhaust brake on one.

Hmm, that's interesting. I've never known/ heard of one to exist.


Cool.

Batty, I have also heard rumors that the new LML Duramax will use the VGT as the exhaust break as well. Should be interesting.

I may be confused, and have read Allison instead of Aisin transmission, but the question remains the same..... now, if i install one on a chevy, and hook a torque converter lockup selinoid up to the exhaust brake switch, so that when you turn the brake on, it locks up the converter, would that be plausible?

batty1214 wrote:

I may be confused, and have read Allison instead of Aisin transmission, but the question remains the same..... now, if i install one on a chevy, and hook a torque converter lockup selinoid up to the exhaust brake switch, so that when you turn the brake on, it locks up the converter, would that be plausible?

You could do that. But it would be easier to install a programmer on the transmission.

batty1214 wrote:

I may be confused, and have read Allison instead of Aisin transmission, but the question remains the same..... now, if i install one on a chevy, and hook a torque converter lockup selinoid up to the exhaust brake switch, so that when you turn the brake on, it locks up the converter, would that be plausible?

You could do that. But it would be easier to install a programmer on the transmission.

merlin5577 wrote:

batty1214 wrote:

I may be confused, and have read Allison instead of Aisin transmission, but the question remains the same..... now, if i install one on a chevy, and hook a torque converter lockup selinoid up to the exhaust brake switch, so that when you turn the brake on, it locks up the converter, would that be plausible?

You could do that. But it would be easier to install a programmer on the transmission.

and why did I not think of that?