Cl713 Posted August 19, 2014 Share Posted August 19, 2014 When I purchased my truck, the dealer told me that the truck originally was delivered with a mack 13 speed, and when the previous owner traded it in, the dealer changed the shifter effectively making it a 18 speed. After doing my research, I found that this is possible and not detrimental to the transmission, my question however; is there a modification or reprogramming that needs to take place with either the eecu or the vecu? Torque limiter? I am plagued with low power and I thought this might be related. The truck runs very strong in the lower gears, but seems to run out of power in high range with even a light load. 1999 cl 713 Etech 460Heavy haul specs 1 Quote Link to comment https://www.bigmacktrucks.com/topic/36752-mack-13-speed-to-18-speed-conversion/ Share on other sites More sharing options...
slpwlker Posted August 19, 2014 Share Posted August 19, 2014 Welcome to the Junglewhat gearing do you have? Also where your at it isn't exactly flat ground but with the Idaho annual I know they give ungodly weight on 5 axles and biggerI'm running a 600 Cat with an 18 and 4.11's and I feel them in high range going up those hills/Mountains. Quote Link to comment https://www.bigmacktrucks.com/topic/36752-mack-13-speed-to-18-speed-conversion/#findComment-256578 Share on other sites More sharing options...
MrCat Posted August 19, 2014 Share Posted August 19, 2014 The only difference is the shift knob, you can take any 13 speed knob, break a small piece off plastic that limits splits and you have an 18 speed. 1 Quote Mike PacittoChelmsford Mass Link to comment https://www.bigmacktrucks.com/topic/36752-mack-13-speed-to-18-speed-conversion/#findComment-256579 Share on other sites More sharing options...
slpwlker Posted August 19, 2014 Share Posted August 19, 2014 The only difference is the shift knob, you can take any 13 speed knob, break a small piece off plastic that limits splits and you have an 18 speed.Don't do it on an Eaton. It will grenade Quote Link to comment https://www.bigmacktrucks.com/topic/36752-mack-13-speed-to-18-speed-conversion/#findComment-256580 Share on other sites More sharing options...
cheeseburg Posted September 30, 2015 Share Posted September 30, 2015 It works fine on a mack 13 speed i have had it done now for 10 years or better love to be able to spit low side Quote Link to comment https://www.bigmacktrucks.com/topic/36752-mack-13-speed-to-18-speed-conversion/#findComment-305669 Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.