I have a 2016 3500 SRW 6.7HO with the Aisin. About 1.5 years ago i noticed a squeal when using the engine brake. Took it to the stealership they said manifold gasket they replaced it and it stopped for like 2 weeks then one day i was pushing her pretty hard and i heard a pop from under the hood on the right side of motor but nothing happened just the pop! After that the squeal got a little worse. Took it to another different stealership they said it was some kind of gasket on the egr! Had it fixed but it still squealed a little when using the EB and from then on it has gotten worse! Exspecialy when pulling my trailer. Now to last week took it to the stealership the first one i took it to they said the manifold is cracked. So i made an appointment it went in on Monday at about 10am they called me said it need a whole new head because 3 of the manifold bolts are broke off in the head!! Now is it common for this squeal my 13 i had did it also but got rid of it before fixing and why would they put a whole new head on it instead of taping out the bolts and putting new ones in?!? Also if the manifold isnt cracked would you think they would replace that also or use the old one! I was told dont let them put the old one on because there prone to warping?