4.8 Timing chain lubrication

**GMJim** · 12-26-2015, 01:01 PM

I decided to change my oil pan in my 68 Chevy short box pickup because the stock 2002 4.8 2WD pick up pan hangs too low, and put another cam in while I was at it and am a bit concerned about what I found when I removed everything.

I bought this truck with the LS 4.8 in it and the previous owner had the engine rebuilt by a reputable engine builder and it has only 600 or so miles on it. When I removed the front cover the first thing I noticed was the inside of the cover had little to no oil on it and the cam gear and chain about the same?? Now it has been in my garage not running for about 6 weeks while I replaced the rear gears, diff and axles so maybe the oil drained down but it looks a little too clean. Second thing I found was what I would call on a Gen 1 or Gen 2 engine a loose timing chain. Now I've done a lot of searching on this site and others and have found I'm not the only one complaining about timing chain slack on an LS even with a new chain and gears. If this were a Gen 1 or 2 engine I would definitely be replacing the chain. I took a video with my phone but can't seem to get it on here. My oil pressure was very good prior to pulling things apart so I'm somewhat concerned about the chain slack. Could it be that it's wearing prematurely because of lack of lubrication or is this normal?

Any feedback would be appreciated.
Thanks
Jim

**0rion** · 12-26-2015, 04:31 PM

1.5 months of sitting will let pretty much all the oil end back up in the pan. I would have to dig out the manual to see the spec for the chain but it's more than you would think....I want to say like 3/8" or something like that. It's a lot.

**GMJim** · 12-26-2015, 05:18 PM

Originally Posted by 0rion

1.5 months of sitting will let pretty much all the oil end back up in the pan. I would have to dig out the manual to see the spec for the chain but it's more than you would think....I want to say like 3/8" or something like that. It's a lot.

Thanks for the reply. It has more than 3/8" but the cam gear only moves maybe 1 degree if that. I was thinking of replacing the chain and gears with something a little better. Some are saying the LS2 chain and gears are better but It would seem that the LS2 chain is what is used on all the earlier engines now.

**pajeff02** · 12-27-2015, 04:31 AM

Agree. Sitting that long all of the excess oil would drip away leaving only a slight film at best.

***SMWS6TA*** · 12-27-2015, 08:11 AM

LS2 timing chain is pretty much the standard for replacement. A double roller would be overkill for that 4.8 unless you where throwing a turbo on it.

Their is also a C5 timing chain that is really good but cost more than the LS2.

If it helps I'm running the LS2 timing chain on my 403ci.

As far as the slack you can get from Trick Flow (TFS-K30675600) timing chain dampener for $50.

Also when it comes time to start the motor, disconnect the fuel pump fuse and turn it over a few times to prime the system.

**GMJim** · 12-27-2015, 10:22 AM

Thanks for the info. This is just a cruiser so no turbo. In fact the reason this came apart to begin with is because the previous owner installed a cam that is just too much for this engine. I either had to replace the cam or get a stall converter. I elected to put the stock cam back in it and noticed the chain slack. Anyway thanks again!
Jim