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12 speed shifting question

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Hi guys,


New here. I just bought an 87 Mack R688st. First, I wanted to say thanks because I was able to fix a bunch of things on the truck just off of the information I found on this forum, so it's been invaluable.


Anyway, I have a 12 speed e6 350. (I'm a new driver)

Having a bit of an issue with the truck stalling, wondering if I should be doing something different.


I turn the truck on. Build up air. Push in the brakes. Push in the clutch shift the truck to 1st direct and then the truck stalls.



My question is:



Should I be revving the truck as I'm letting off the clutch to get into 1st gear?


Do I need to rev up a certain rpm?


I.e. shift into 1st at 1200 rpm?


Thanks guys

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1st direct is High range. isnt your shift knob round with an air switch that goes sideways? 4 positions. lo-direct, nuetral and reverse.

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stuck brakes for sure can do this.. Was a brake chamber replaced right before this and the lines were switched?   I'm trying not to throw out a dozen things on this thread. I bet its a simple fix..

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My 2 cents worth sez (Tax FREE)

the engine brake is on or short n out n try n 2 stall the cold motor

it twould make the engine sound like crap


There again

Wot Would eye kno



Edited by Swishy
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I think we're missing some more details. We don't have acknowledgement that hes releasing the parking brake.  When did the truck roll last? Has it been sitting for a long time? What work did you have to do on it?

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