7/15/2019 · L5p down shifts hard . Jump to Latest Follow … I noticed my 2019 seems to want to hit each gear down shifting when coming to a stop and it seems to be a noticeable down shift. Almost like when in hill decent mode. … experienced hard downshift into first gear when braking hard and a not “smooth as butter” shift from 3-4 like all the other …
10/22/2018 · I’ve got 4000 miles on my 2018 2500 diesel. Every once in a while I get a hard shift when getting on the freeway at a gradual acceleration all shifts are smooth and then one will Bang into gear. I’ve also had the same similar issue on down shift while braking to a complete stop all down shifts…
I have a 2017 L5P and rebuilt the transmission with a stage 3 suncoast kit this summer. Haven’t had any issues for 6k miles and all of the sudden I’m getting hard downshifts from 4-3-2-1 and my 5-4 downshift has produced a howl. None of this is consistent though. Changed the spin on filter to…
12/13/2018 · The L5P diesel engine is matched to an updated Allison 6-speed transmission (Fig. 10) that’s designed to accommodate the engine’s higher torque capacity. Fig. 10 Following are several operating characteristics of the 6.6L Duramax diesel engine and Allison 6-speed transmission that should be considered normal operation.
3/25/2018 · Mine will occasionally give a very firm downshift at slower speeds, usually when I’m hard on the brakes. Not sure if that’s the same as the clunk that the OP is referring to. It only does it once in a while on my truck. At first it alarmed me a bit, as it does seem to hit pretty hard .
12/20/2018 · I bought a 2017 GMC Sierra Denali 6.2 and at about 12K miles I started noticing a hard shift and down shift when in slow traffic as the truck hits 10 mph. I took the truck into the dealer and they found it had an internal leak caused by a faulty seal, they replaced the seal and told me it was fixed.
Fits Chevy/GMC Duramax 6.6L L5P (2017-2020) 2500HD & 3500 Horsepower Select Knob: *Stock*30 HP – Heavy Tow*60 HP – Best Mileage and Tow*90 HP – Mileage and Light Tow BENEFITS OF PRO MODULE Simple Install: EZ Plug-n-Play technology that you can install in minutes by simply connecting to your engine’s wire-harness, 9/21/2005 · Smoking during down shift usually means valve seals, oil being drawn through intake valves seals under vacuum. This is just an educational guess as I’m not looking at the car. Bruce. Sep 21, 2005 #5. dsm_illicious Proven Member. 234 1. Joined Aug 6, 2002. A City, California.
Allison had to put a new trans in my brothers L5P at 4K miles. It was doing the same thing. level 1. bob_ert91. 1 point · 5 months ago. Does the truck lunge forward or does your body lunge forward like a hard downshift ? level 2. Idiotfiasco. Original Poster 1 point · 5 months ago. It’s definitely the truck. It did it today slowing in the turn …
2/14/2012 · My 6speed Allison in my Chevy 2500 shifts really hard when I floor it to pass at 40-50 mph What is the problem? I – Answered by a verified Transmission Mechanic. We use cookies to give you the best possible experience on our website.
