Break In Period

[Jansen]

Does anyone know the break-in period for the 5.3L? I bought a Z71 GMC Dec/29/2004 and currently have 1700 miles on it. I'm a fan of mobile 1 full synthetic. The dealership told me to wait 30,000 miles, yes 30K, before switching from conventional to sythetic. Anyone buy this?

 

 

I was also told not to undercoat my truck due to GM's undercoating and possible warranty issues.

 

Jansen

 

2004 GMC Sierra SLE

5.3L V8 4x4 4.10's

Marine Metallic Blue

[facn8me]

Change any time you want. The Vette comes factory with full syntho in it. Get new dealer. You do not want the person that said wait 30k to have anything to do with servicing or repairing your vehicle. RUN to a different place for warrenty work.

[Jansen]

I'm inclined to agree with that statement. Mobil 1 at 3,000 miles it is.

[Mighty HD]

I put mobil 1 in @ 500 miles, then changed it again @ 2000 miles. At 2000 I changed everything to syn...front/rear end to M1. Transmission will be soon. I change it every 2000 miles. I don't drive it much so it dosent hurt anything doing it every 2k.

[lrymal]

I'm inclined to agree with that statement.  Mobil 1 at 3,000 miles it is.

 

<{POST_SNAPBACK}>

 

 

Yes. Total agreement.

Regarding the undercoating.... don't do it. In the old days, we undercoated big time but no more. Improved corrosion resistance on today's vehicles doesn't lend itself to the need for it. But, more importantly, anti-corrision sticky sprays can clog up the drain journals, especially in the rocker panels which can indeed cause them to rust due to trapped moisture.

 

However, in concert with this, if you live in salt states or on the coast and have to hit the sands and likewise, salt-covered winter highways, I'd certainly do an aggressive underspray annually. Again, undercoating could potentially trap some of the salts.

[budhayes3]

Complete agreement with all. I switched to Mobil1 at about 650 mi and haven't looked back. As far as undercoating...or "soundproofing" as some dealers have been forced to call it goes, ... it's a scam.... might as well get a stem lube and also stock up on bumper fluid. Put an order in for the high performance filopadator valve.

Undercoating creates more problems than anything...especially if you plan on servicing the vehicle...that crap will get all over ya and stay on.

[MS3DALE]

You'll be fine with Mobil1 at 500 or 3,000 miles if you want.

And I totally agree with everyone else on the undercoating...DON'T DO IT!!!!