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View Full Version : Valve lash mileage?



DickWells
10-28-2015, 18:47
A few weeks back, I posted a question on this, as my truck now has 182 K on it.
Got no responses, and went back through my books to try and pinpoint a scheduled valve adjustment interval, with no info found. So, last week, I stopped in at the local Chevy dealer and asked the same question at the service desk. The manager had never heard the question, so he went to one of his three diesel men. The mechanic has over 15 years with this dealer, and has never done a Dura Max in the 14 years that they've been on the market. So, I guess I have my answer. If my DM isn't clattering like crazy, then I guess I'd better stop fretting about it and go on my merry way.

a5150nut
10-29-2015, 05:51
But Dick, if just wanting to spend some $$ I am available for donations!

But thank you for the information.

Kennedy
10-29-2015, 07:27
I had a 2014 LML in last week with 246k on the clock. I'm quite certain that it was never apart.

DickWells
10-29-2015, 18:19
Thanks, John. That info adds even more comfort to my tired old ears.

I do know that the valves were checked each of the two times that the injectors have been replaced, once at ~68 K and again at ~120 K miles, and found to not need adjustment either time.

Good to know that these engines are apparently holding up very well, internally.

More Power
10-30-2015, 09:59
I always thought it interesting that GM did not include a valve lash adjustment interval. Nearly every motorcycle has a recommended schedule - partly for wear in the valve train components as well as valve recession into the valve seat.

Roller valve lifters and high oil flow/pressure reduce wear, and it may be that the valve & seat alloys keep recession at a very low level. And, I suspect engineers count on engine service (head gaskets) at some point, which would provide an opportunity to redo the valve clearances.

DickWells
10-30-2015, 17:36
My Can Am Spyder service manual calls for a check every 8,000 miles, IIRC. Since it's an overhead cam engine, we expect the valve lash to decrease. So, I checked my own at about 8,000+, and found them to be within spec. Since then, I've talked to a lot of Spyder owners on Spyder Lovers, and in person, and found no-one who pays much attention to that 8K interval. Some have reported over 50K miles without having the valve covers off. So, I've quit worrying about that one, too. Some difference, from a glance back in my mind to my first car, a 40 Chevy stovebolt coupe. Oh, but how I wish I had put that thing up on blocks, and could bring it back to life, today! Such is hind-sight, I guess. Sorry. Wrong forum, but just had to wander back to the good old days for a minute.

rapidoxidationman
10-30-2015, 18:59
Every 8K on a Spyder, eh? That isn't too bad. The old Benz 300D in my driveway gets an inspection/adjustment every 15K and is easy to do in just a couple of hours hood up to hood down. My Ducati has to have the valves inspected every 50 miles or so and it is decidedly not easy but shouldn't be nearly as time consuming as a duramax.

Ok, maybe only every 6K... Tira Misu will be living in my dining room for the winter, showcased like the piece of Italian Art she is. Her first valve adjustment under my wrenches will happen sometime over the course of the next 6 months of cold. Loose valves will just rob a bit of power. Tight valves will burn down a head or maybe just fry a valve seat:eek: