Oil questions, 1995 Silverado 5.7L

[jhellwig]

Originally Posted By: GRWOil


There is a slight pooling of oil on the top of the motor next to the left valve cover, it fills back up if I wipe it away. I replaced the valve cover gasket, and nothing changed. When I had the cover off, I didn't see any varnish. looked new aside from a splash of oil in the corner. I have no idea where that oil is coming from. The rear main seal isn't leaking, and the bottom of the engine is relatively clean oil free.

Mine does the same thing. Not a clue where it comes from unless it drains off the throttle body where the crank case vent hooks into the spacer.

 

[KenO]

It's a small block - keep oil in it and it'll run forever. What you run isn't a huge deal. When you DO drive it though, make sure it gets at least 1 good long drive every few months, even if it's towing something. My '97 C2500 has 390k on the odometer. Make sure the coolant is flushed on a regular basis, and you'll have no troubles over the next decade or 2. This is a TBI motor, so no intake gaskets to worry about, but keep Dexcool out of it.

 

[GRWOil]

Originally Posted By: wtd
Any conventional oil will last the year with those miles. You don't need to waste the money on a synthetic. I have two 98 chevy trucks that only go about 3,000 miles a year each and have mainly run a conventional most of the time. My 98 K1500 with the 5.7L is only running Trop Artic 5W-30 blend because I got it very cheap on sale. The 98 K3500 with the 7.4L uses Pennzoil HM 5W-30 because it had a couple of small oil leaks.

As far as your hot start issue, when was the last time you changed your coolant or your thermostat? Does your truck run hot? When was the last time it had a complete tune-up?


It had a new thermostat 10 years and 50k miles ago. It's never had coolant flushed/replaced, but it's had a very slow coolant leak since new, so gets a slash of top off antifreeze every so often. It has never run hot, or even close to it. Once when towing with my foot to the floor it got up to 220F when it normally runs 185F. Don't think it's ever had a tune-up, at least not in the past 10 years.

 

[Alex_V]

Plugs could likely be at least part of your hot start problem - wires and cap/rotor can last longer, but depending on the plugs it has in it they could have deteriorated over that last 10 yr./50K enough to cause hard starting. I've replaced 4 or 5 sets of plugs in the last several months and every one of them ran well - once running - but to varying degrees were hard to start.

 

[GRWOil]

Originally Posted By: Alex_V
Plugs could likely be at least part of your hot start problem - wires and cap/rotor can last longer, but depending on the plugs it has in it they could have deteriorated over that last 10 yr./50K enough to cause hard starting. I've replaced 4 or 5 sets of plugs in the last several months and every one of them ran well - once running - but to varying degrees were hard to start.


It had platinum plugs at 55K ago, maybe I should pull one and take a look at it.

 

[wtd]

Originally Posted By: GRWOil
Originally Posted By: wtd
Any conventional oil will last the year with those miles. You don't need to waste the money on a synthetic. I have two 98 chevy trucks that only go about 3,000 miles a year each and have mainly run a conventional most of the time. My 98 K1500 with the 5.7L is only running Trop Artic 5W-30 blend because I got it very cheap on sale. The 98 K3500 with the 7.4L uses Pennzoil HM 5W-30 because it had a couple of small oil leaks.

As far as your hot start issue, when was the last time you changed your coolant or your thermostat? Does your truck run hot? When was the last time it had a complete tune-up?


It had a new thermostat 10 years and 50k miles ago. It's never had coolant flushed/replaced, but it's had a very slow coolant leak since new, so gets a slash of top off antifreeze every so often. It has never run hot, or even close to it. Once when towing with my foot to the floor it got up to 220F when it normally runs 185F. Don't think it's ever had a tune-up, at least not in the past 10 years.

I just had to replace the thermostat in my 98 with the 5.7L last year because it had been about 10 years since it was last replaced and it was sticking open to the point that it was causing a high idle even after the truck was fully warmed up.

I would do a full tuneup on it because sitting around can cause issues with parts. I have had the contact points in my truck's distributor corrode to the point that the truck would hardly run due to sitting a lot. I would also change the coolant even though you top it off occasionally.