so I let my new trailhawk warm up till rpm is down to 800/900rpm little click when putting in reverse...but you shouldn't have to wait that long on a new jeep.....do to emissions they suggest a minute or less is fine so we were in a hurry started it up rpm was at 1500/1300 rpm put into reverse and a very loud clunk....drive line slop or so many things it could be...I wonder if there is a update to lower initial torque when cold/high rpm to softn the clunk....anybody have this clunk or had it fixed....thanks guys/gals
I let mine get down to about 1100 before taking off. I notice the hard shift some of the time but not always. It has been better since having my transmission replaced for another not related issue. The colder it gets the longer I will let it warm up before I put in reverse now that the fall and winter is upon us. As far as updates...there are periodically flash updates to the computer that may need to be installed every time when getting an oil change at regular maintenance and service intervals. My transmission has been flashed 3 or 4 times.
yeah when I let warm up and rpm drops to 1000rpm it doesn't do it........yes I will ask for trans update when I get my first oil change...the only thing with that is other things change...like my hemi 8sp was clunking coming to a stop so they flashed it and I lost my aggressive trans mapping they have for the r/ts trans for performance it soften the shifts......so it's a teeter/totter...get one thing and lose another....so might just keep letting it warm up because other than that the trans runs flawless.....oh well it's always something......thanks r/g hawk
I would say it's a motor mount issue. I have a 2018 Renegade Latitude 4x2 9speed auto with the 2.4. I also get that clunk when putting in reverse after a cold start. I keep my Jeep in the garage most of the time and the temperature never really changes much here. But almost always after a cold start I get that knock and clunk when starting and letting it run for a few minutes then shifting to reverse. I'm pretty much sold on the fact it might be a motor mount issue when I had to back out of the entrance to the parking garage at my work the other night. It's at a fairly steep incline and the darn badge reader wouldn't let me in so I had to reverse out. When I put the transmission in reverse and mashed the pedal a little, I felt and heard that knock/clunk along with a strong vibration as I backed out of the inclined entrance. ZACC has about 13,000 on the clock without any issues, besides this weird one
Could be gear binding, maybe try to engage the parking brake before putting the transmission in P. Also helpful to put it in N, set brakes, then P.
