fredster

I tend to do a lot of my own maintenance. I have had my 2007 Tahoe for just over a month and did my usual early oil change at 1000 miles and again at 3000 miles. While I was under the truck I looked for zerks on the front suspension/steering and did not find any, at least not in any of the places they were on my 1998 and 2003 Chevy pickups. The 98 truck had 12 zerks and the 03 had 11. So....are they in weird places or is everything sealed up and "lifetime lubricated"? I have searched high and low on the Internet and this topic does not seem to have come up. I usually do a greasing early on because I have found that the factory doesn't always "fill" the inside with grease. Keeping the joint full of grease helps keep out moisture which contributes to longevity. So if there are zerks in there I would really like to know about their location.

BTW...the oil came out pretty dirty at 1000 miles and was actually dark again at 3000. The darkness at 3000 really surprised me.

Thanks!

ZX1100F1

No Zerks, GM calls this feature a "Lubed for life" chassis.

Don't be too shocked about the oil being black at 1k and again at 3k miles, these motors are tight but there is still tons of blow-by past the valve seats/guides and piston rings for the first several thousand miles, this is very normal and nothing to worry about as long as you aren't consuming more than 1qt between oil changes.

By 10,000 miles you will notice improved performance and economy and the oil will take longer to darken.

fredster

Thanks for the information. Any general expectations on the longevity of "sealed for life" bearings? I would hope 100K or more but am curious as to what to expect.

That is a good tip on the oil & 10K break-in, too. My MPG's are still not what I expect (15-15.5 mixed commute; 17-18 highway) so at least I have something a little better to look forward to in that area (hopefully).

Thanks!

ZX1100F1

The designed test life for these components is <150,000 miles under normal usage.

These sealed components have been holding up well and aren't anything new, they've been around for years on various products.
The skinny is that most people don't maintain they're vehicles the way they should, so for that average Joe, these parts will do well.
They are also better at keeping out contamination (salt, dirt etc) which can ruin a joint or bearing faster than lack of lubrication.

Even for those people that follow a strict regiment of regular scheduled maintenance and keep the zerks well greased there is a tendency to over-grease which stretches the rubber seals and allows contamination in and the grease to escape out.

We estimate that fewer than 5% of consumers properly grease the chassis, which is to use the proper (EP) grease at each Zerk just until the rubber seal begins to expand and at an interval of 3k miles or 3 months.

With all that said there is always room to debate this issue.

swatson1

Since we're on the topic, when should I do my first oil change for my LTZ? I now have over 5,000 miles, but the oil life is still above 40%. My Onstar report (emailed to me) says I do not need any service yet. Seems like a lot of miles to not have an oi change yet...

ZX1100F1

Change it right away, your first oil change is best if done around 1,500 miles.

73shark

Mine has a zerk on the outer tie rod ends. Is that a change?

ZX1100F1

You are correct, the tie-rod ends have zerks, not a change just my mistake.