My LS1 rebuild is done!

[Chris B.]

I just got her back and she seems to be quieter. The "slapping/knocking seem to be gone but I have not had the chance to do a cold start as it was warmed up when I picked it up today. It used to slap when hot though so I think it is fixed and time will tell if the new rings get rid of the oil consumption.
I think I'm going to change out the Mobil 1 5w30 the dealer put in to Halvoline for break in. I'm not sure the dealer put in M1 as it is super clear on the dip stick, more clear then I remember M1 in past changes so they could have put in a dino oil and told me it was M1 to keep me "happy". I think I'll change it right away to make sure I know what it has in the engine for break in. Halvoline seems to be a top dino oil and should be good for breaking in the new engine! I plan on running dino for 3,500 miles(changing it 3 times durring this time) and then switching back to Mobil 1 10w30.

 

[1 FMF]

I would leave the oil they filled it with in there for 500-1000 miles. When I've been at the dealer, I noticed in their fluid display case a bottle of GM engine oil break-in additive. I wasn't able to read the bottle, nor did I ever inquire about it but I think it has to do with piston ring wear in. You might want to check with the dealer about that before you do anything. If that's in the oil now, probably wouldn't be a good idea to change oil early and run the engine without that break-in stuff. Again, that's if it's needed depending on the extent of your rebuild, I don't know. Good luck with the new motor

 

[Patman]

Hopefully they built you a nice strong one, it sounds like they did a good job so far though!

Any chance that you'll try out mixing 2qts of M1 15w50 with 4qts 10w30 in order to thicken up the mix? I know the LS1 likes slightly thicker oils, and it would be nice to see a UOA of this mix in the LS1, since it's very common for guys to run this combo.

 

[Chris B.]

I would try it. I talked with Terry and he have me some good advice about the break in. I'll ask him what he thinks of it. I need to find out if I should dump the M1 the dealer put in for break in. I'm not driving it till then.