PovertyZ28

Probably in the wrong section but...my 01 z28 I picked up a few months ago has nearly 220k miles and considering the BS paperwork that was handed to me during the trade, I don't believe it's got a 90k mile LS1 in it...which leads me to believe that other stuff hasn't been done as well. With that being said, basic datalogging has shown that I had a bad alternator (been replaced) and that it also has a bad o2 sensor and knock sensors. Those are all relatively easy fixes along with some gaskets that need to be replaced, but the bigger question is: What else should I tear into and look at? The car is basically stock aside from a gear, some very tired adjustable rear shocks, gutted cats, a muffler delete, and I strongly believe a very broken tune. Should a compression test and leakdown test be considered in my to-do list? What else should I consider doing to get it in as good of shape as it can get to start working towards a build of some sort?

G Atsma

These engines go WAY past 200k miles all the time. First things to do are fix all that's obviously wrong with it. THEN reassess the situation and go from there.

.boB

iTrader: (1)

Absolutely! Why wouldn't do that? Although it's not the end all-be all, it will certainly give you some good information. If the oil hasn't been changed yet, also consider a UOA.

99 Black Bird T/A

iTrader: (4)

Welcome to the high mile LS1 Club

There are a lot of LS engines that go well over 200,000 miles and still J have a lot of life in them. Here's mine 247,000 mile 02 Z28 Daily Driver The 02 Z28 has proved reliable after a little extra maintenance and does 1,300 mile road trips on occasion. Collecting performance parts for a couple of upgrades now.

For your car given the background description I would do a lot of general maintenance and figure out the actual condition of the car. Assuming things check out I would consider getting the car tuned. Bad tunes are bad news and can cause all sorts of issues. However, if the maintenance has been neglected that may be an issue.

I'd take the same approach as with my 02 Z28. It's time consuming but necessary with any older high mile car in my opinion. The fun starts after getting the stock car correctly sorted out.

Check the brake components, pads, rotors etc

Check all the fluids and see what they look like.
Check for leaks. Rear end pinion seal is prone to leak.

Change engine oil & use a quality filter. I like the Napa Gold truck filters because they are bigger. I'm a Mobile 1 customer but Penzoil Ultra has a hard hitting detergent package great for cleaning. Check oil level at each gas fill. The valve seals are probably shot and allow the engine to burn oil. It's common and a fairly easy fix.

4L60e - Drop transmission pan and dump fluid. Replace filter, check magnet. Check for band material etc. New filter and standard Dextron III transmission fluid. Do this a couple of times. Say 500miles and then 500 more. Fresh clean fluid and filter helps.

Change the differential oil.

Coolant flush & new coolant, brake fluid flush & new fluid, same for power steering.

Decarbon treatment - professional grade GM X66

New air filter and new fuel filter

New plugs & wires

Check PVC hoses carefully, they often Crack at the back of the engine and may need replaced.

Evaluation how car runs, have car tuned etc

Getting tire rotated and balanced may help. An alignment is probably in order.

gesto

Change oil and plugs, add a high stall torque converter and go WOT all the time. That'll fix it up.

Joey D

iTrader: (4)

Jus picked one up with 360,000 even. 100% stock. M6

99 Black Bird T/A

iTrader: (4)

Sweet, you should start and thread and post some pics. TA or Z28, or?

Joey D

iTrader: (4)

z28. Wil prob friday thanks

Summitracing

The good news is the short blocks on these are good for a long long time. The top end is transferable to a new bottom end. Trunnions, valve springs and lifters are toast, but the good news those are things you would normally fix while you are doing a cam swap anyway. What kind of behavior are you looking for and what are you wanting to do with the car?

Polyalphaolefin

That mileage isn't too terrible. I recommend using Mobil 1 High Mileage 10w-30 with a Fram Ultra filter. Change it every 5k miles for a couple OCIs and then try 7.5k or 10k miles.

Contrary to popular belief, no oil cleans better than any other. The detergents don't scrub away sludge and varnish like cleaner in a toilet bowl. The detergents exist to keep the oil clean, not the engine. Pennzoil Ultra and Mobil 1 tend to have higher detergent levels due to their use of natural gas (GTL) base oils having a lower natural TBN than hydroisomerized group III or PAO group IV base oils.

Avoid any aftermarket additives like STP, Slick 50, Lucas, Seafoam, etc... They're mostly gimmicks that don't work as advertised. Many of them have been under fire by the Federal Trade Commission for false advertisement at some point or another.

G Atsma

Slick 50 is still around? What a scam that was....

sjsingle1

iTrader: (1)

slick 50 ? I use Prolong !!!

Polyalphaolefin

Sadly, Slick 50 is still around with just different (vague and misleading) advertisement to keep them out of the FTC's radar. It's still the same scam in a bottle.

https://www.ftc.gov/news-events/pres...ainst-slick-50

Prolong is right up there with them.

https://www.ftc.gov/news-events/pres...es-ftc-charges