X15 tractor vibrates when engine brake is on

[Edjahman]

579 Pete with an X15 Cummins. 2018

It just had a new cam put in it around Thanksgiving.

I don't know if this is related but when the engine brake is on, especially when loaded it'll shake then it'll be normal. It seems much worse on all 6 cylinders as expected.

It seems to be intermittent.

Also I noticed when driving really slow in heavy traffic the engine brake feels like it's on with the switch turned off slightly when I remove my foot from the accelerator but maybe it's my imagination.

I just purchased this tractor so I'm getting used to what feels normal.

Thank you

[Chamberpains]

Is this thing tuned or demandated in any way?

I saw in your other posts that this truck is taken to a Peterbilt dealership to have work done. This could be your problem right here. There are hundreds of people on here that nothing but horror stories about how a dealership screwed up.

If I were you, I'd get on https://quickserve.cummins.com/info/index.html and register your engine for free. Start learning how to run the overhead adjustments on that exact engine, gather a few tools and start checking things out with your own eyes.

Dealerships are ripe with big headed bafoons that think they know it all and yet screw up every procedure in the book or take detrimental shortcuts. All because they got a little bit of training, that they probably didn't take seriously or listen to fully.

If you value your business and that truck, then start getting dirty and getting hands on with it. Now-a-days it's the only way an O/O can survive. Dealerships will bleed you dry real fast. Leaving your equipment broken and you broke. They won't give a damn when you cant feed your family or take care your responsibilities because they were to inept to do a job right.

[Waterloo]

I would pop the top and see if they put everything back, and check the torque on the bolts holding the valve train together. Pray they did not install with an air gun... And run an overhead. More than likely, like CP said, they screwed something up. Hell, my dealer installed all of the wrong parts in my 871 when they in framed it, and did a lousy job to boot. Me and Rawze tore it all apart and in frame'd it again!

[Rawze]

also want to do an injector leak test on it .. could be a leaky injector...

[JimT]

If you have Insite, you could also try a cylinder cut-out test. Make sure your actually running on all cylinders. Although given the recent repair I'd definitely be thinking along the same lines as Chamberpains and Waterloo. Gotta make sure someone didn't screw up.

Also, I gotta wonder if what you're feeling now could be related to the true cause of the cam needing to be replaced?

[Edjahman]

Yeah I understand. Thats why I'm learning really quick.

Thank you

[Edjahman]

It's going to Peterbilt Monday for a DEF cleaning.

Hopefully it'll get sorted out then or I'll sort it out myself.

Thank you

[Waterloo]

I would at the very least get under the top of the motor and poke around, even a good visual, there may be something not tight or a broken bolt or worse rolling around in there.

And inspect the cam shaft lobes/rollers yourself. If there is something wrong under there, the dealer is going to try to blame you for the damage, so be prepared. We have all been there and done that. They tried the same with me and that in frame, when we pulled the parts and saw that they did not belong in my motor, well the tables turned.

[Edjahman]

OK thank you for your reply.