Felix C

Recently noticed an increase in the reported number of LS1 and LS2s oil pump failures among the GTO crowd. Is this a known weak point in the LSx?

At what mileage should the oil pump be replaced from the point of view of preventive maintenance?

TrikeMike

iTrader: (7)

I'm still on my stock pump. 2000 ls1 with 127k miles on it. I've done 2 cam swaps in it too. Doesn't seem to be a weak link for me, but if you ever do a cam swap its not the worst idea to go ahead and do the oil pump.

autogeek23

iTrader: (13)

I have heard the same thing. a friend of mine had a 99Z28 and he didnt change his and it went. same friend also told a guy last year to change his oil pump at 140k mi on his 99 camaro and he got a call from his this year with a rod knock. when i got my trans am (157k mi) he insisted i change my oil pump so i did after having the car a week, along with the pressure sending unit for good measure. now i never worry

LS1-450

iTrader: (33)

Never heard of it. Perhaps, since the GTO is based on the Australian model, maybe different material was used in manufacturing the gears within the pump
or maybe the same can be assumed regarding the spring material used in the pump. Not knowing what has failed, can't really say. Suprising to hear of a gear pump failure. Would lean toward a spring issue over as gear issue, though, ie; spring braking & then the spring parts chewing up the gears within the pump? What part of the pump is failing?

Felix C

Not that much data other than oil pump failure. A few folks have gone into detail enough to mention the spring was in the "open position" but do not know what that means never having seen an oil pump for this engine.

slammedc5

iTrader: (1)

Hum, seems to be a solid pump. On Corvette forum, ( not my favorite forum) there's a high milage thread, there's guys with 400,000 plus miles, alot of 300,000 mile cars, etc. I just did a cam swap on my c5, my pump was fine, I replaced it with a new ported ls6 pump, only because it came in the cam kit. Now theres plenty of issues with people not installing the o ring correctly in the pick up tube, resulting in low pressure. Its very easyto install actually, but maybe the quality control and assembly was different with the GTO, I don't know. The oil pump is one of the many things I don't ever worry about with my motor.

crainholio

iTrader: (2)

It's hard to trace the root cause of the failures without knowing which component failed and how it did so.

The design flaws in the original LS1 oil pump were corrected by the time GTOs were being built. However, as with any mass-produced assembly defects are possible.

It would be useful to know if the failed pumps were factory-installed vs. having been removed and re-installed without proper alignment.

ls1 1990 VN

These pumps do appear to be way more tempermental than the old Gen 1 oil pumps....they do produce a way higher psi though.

LS1-450

iTrader: (33)

They're really not. That's why we've asked for detailed information about the "GTO forum" oil pump failures. We need details...

-engine is spun up to x,xxx RPM
-engine has previously overheated
-stock pump
-ported pump or otherwise modified
-etc.
-shimmed spring
-oil additives used
-varnish/gunk build up as a result of improperly maintained oil

Not suprised to get confirmation that it's spring related, "spring stuck open." Although, "spring stuck open" is a spring failure not a pump failure. Springs are hardened steel & are more prone to manufacturing related defects.

Doubtful, that the pump itself is the issue. Gear pumps are very reliable.

ls1 1990 VN

Sorry! But they really are!!!!

I grew up with the Gen 1, and apart from installing a new pump on a rebuilt engine etc, oil pumps were NEVER an issue...UNLIKE what we are seeing so often now.