RCMAN46 wrote:
I recommend no towing for 500 miles like you are going to do.
Some say it is not necessary. But there is no way it can possibly do any harm. But if you have one of those 1 in 1000 rear end gear sets that is a little off the 500 miles will allow the gears to wear in with no damage.
Also if you go easy on the engine it is much less to burn oil. No steady state cruising and no cruise control for 500 miles. Vary the engine rpms when cruising.
With my new engines I also change the engine oil at 500 miles the first time. I will get flak for saying this but again there is only one thing it can hurt and that is my pocketbook. But with a $40,000+ vehicle I do not take chances.
I agree with most of what you say. One additional thing I recall with a GM truck I bought new a few years ago.
In addition to no towing for the first 500 miles, my manual also indicated that the first towing 500 miles...I should not exceed a speed of 50 mph...to allow the powertrain to bed in....while towing under load.
I observed this condition when we first towed our trailer. I planned our route out carefully and drove down B roads...less traffic...during the first 500 miles towing.
Our tow vehicle already had about 5000 miles of non towing activity on it, before we hitched up.
Think GM was referring to the break in in of the drive axle. But that's just my guess.