Silverado engine problem

[rshunter]

Originally Posted By: JimPghPA
A clogged PCV valve will cause an engine to sludge up.

I would have hoped that they would have checked for it when they repaired the engine. Then again, this is a dealer that thought synthetic oils were trouble...

 

[tsduke]

On my 05 5.3 the pcv isn't even replaceable or doesn't have one. I've asked 2 GM parts depts and looked online at the major parts stores...nothing. Is it replaceable on the 07?

 

[Loobed]

Originally Posted By: markhait

They said most trucks that run on synthetics have the most engine problems that they see. Again, I don't believe in too much of what they say, but it has got me thinking though.



Your Silverado has a GM/Chevy designed engine. The same basic design as the Corvette or Cadillac engines, and those engine use synthetic oil from the factory. Why would a "truck" engine have problems with synthetics when the car engines do not?

 

[OVERKILL]

Originally Posted By: tsduke
On my 05 5.3 the pcv isn't even replaceable or doesn't have one. I've asked 2 GM parts depts and looked online at the major parts stores...nothing. Is it replaceable on the 07?


IIRC, it should have the "fixed orifice" PCV assembly. Which should still be checked to make sure it is free of build-up.

 

[SigShooter]

I think what the mechanic was trying to say was that when customers use synthetic oil they let it go to long before changing and then problems develop. Look at this guy 3 oil changes in 70000 some miles. No wonder.

 

[INDYMAC]

Exactly how do you check this "fixed orifice"? Where is it? My daughter's 2008 Avalanche 5.3L apparently doesn't have a PCV valve either.

Originally Posted By: OVERK1LL
Originally Posted By: tsduke
On my 05 5.3 the pcv isn't even replaceable or doesn't have one. I've asked 2 GM parts depts and looked online at the major parts stores...nothing. Is it replaceable on the 07?


IIRC, it should have the "fixed orifice" PCV assembly. Which should still be checked to make sure it is free of build-up.

 

[ottotheclown]

That I think is the answer to this thread without full facts. 24,000 mile oci is nuts.

Originally Posted By: SigShooter
I think what the mechanic was trying to say was that when customers use synthetic oil they let it go to long before changing and then problems develop. Look at this guy 3 oil changes in 70000 some miles. No wonder.

 

[markhait]

Originally Posted By: SigShooter
I think what the mechanic was trying to say was that when customers use synthetic oil they let it go to long before changing and then problems develop. Look at this guy 3 oil changes in 70000 some miles. No wonder.

No wonder what SigShooter? Amsoil has extended drain interval of 25k miles! Read their web site....
I stayed within their spec so back off! If you can't run it 25k miles then Amsoil shouldn't make that claim. I just found this site and never heard of a oil analysis before. I'll get one for sure before I do any kind of extended drain again. How about helping me instead of bashing me!

 

[RISUPERCREWMAN]

This is a perfect example of why it is absolutely crazy to do a extended OCI! I change out my Synthetic Oil at 5K mile or 6 month intervals! What ever comes 1st! No exceptions! No matter what oil I'm running! Case Closed! Vehicles are just too darn expensive today to play the 'Gee. let my try the extended OCI game!".....Sorry but Amsoil Marketing is a Scam! AmScam!!!

 

[ottotheclown]

There are alot of claims made that are lies. Either way you see now and all of just should move on with the New Year.

Originally Posted By: markhait
Originally Posted By: SigShooter
I think what the mechanic was trying to say was that when customers use synthetic oil they let it go to long before changing and then problems develop. Look at this guy 3 oil changes in 70000 some miles. No wonder.

No wonder what SigShooter? Amsoil has extended drain interval of 25k miles! Read their web site....
I stayed within their spec so back off! If you can't run it 25k miles then Amsoil shouldn't make that claim. I just found this site and never heard of a oil analysis before. I'll get one for sure before I do any kind of extended drain again. How about helping me instead of bashing me!

 

[Pablo]

Originally Posted By: RISUPERCREWMAN
This is a perfect example of why it is absolutely crazy to do a extended OCI! I change out my Synthetic Oil at 5K mile or 6 month intervals! What ever comes 1st! No exceptions! No matter what oil I'm running! Case Closed! Vehicles are just too darn expensive today to play the 'Gee. let my try the extended OCI game!".....Sorry but Amsoil Marketing is a Scam! AmScam!!!


Calling names is what BITOG is all about. We have solid proof this engine even had sludge? Or perhaps a coolant leak? As we know GM's never have coolant leaks.

People "Experts" just LOVE these few examples (some in this thread wait to pounce).....we don't even know enough to say, perhaps for this usage Amsoil recommends 15K/12 months, but no, the oil is condemned immediately.

http://www.amsoil.com/lit/g1490.pdf

BTW Which Amsoil 5w30 are we talking about?

 

[markhait]

100% Synthetic 5w30 Motor Oil (ASL) This is what I was using.
How do you know when sludge is building up? I'm no mechanic.

 

[Pablo]

Originally Posted By: markhait
100% Synthetic 5w30 Motor Oil (ASL) This is what I was using.
How do you know when sludge is building up? I'm no mechanic.


Thanks. In your case I would have recommended 15K or six month intervals. Frankly I'm not sure why they replaced the push rods, even if there was sludge. The easiest way to get a good view on the top end is to remove one of the valve covers.

First thing I would do right away is a used oil analysis. It won't tell you everything, but if you have a coolant leak the analysis should indicate it with glycol/ antifreeze and/or elevated K/Na.

If you had sludge did the mechanic show you or recommend some cleaning?

 

[SigShooter]

I don't care about Amsoil oil or their website. Maybe you should contact them to get them to reimburse GM for your engine problems. After all they guarantee it for 25000 miles. PT Barnum said their is a sucker born every minute.

 

[markhait]

Originally Posted By: Pablo
Originally Posted By: markhait
100% Synthetic 5w30 Motor Oil (ASL) This is what I was using.
How do you know when sludge is building up? I'm no mechanic.


Thanks. In your case I would have recommended 15K or six month intervals. Frankly I'm not sure why they replaced the push rods, even if there was sludge. The easiest way to get a good view on the top end is to remove one of the valve covers.

First thing I would do right away is a used oil analysis. It won't tell you everything, but if you have a coolant leak the analysis should indicate it with glycol/ antifreeze and/or elevated K/Na.

If you had sludge did the mechanic show you or recommend some cleaning?

Whats a used oil analysis? They didn't show me anything, but they said that they tore the engine apart and removed all the sludge. Thats kind of why I think I have that dreaded piston slap. For the dealer to take 2 days and take the engine apart and keep finding things to be replaced, I suspect that there are bigger issues that GM doesn't want to pay for and so they replace enough to get you running again. I've read on several forums that the engine should be replaced if you have piston slap.
What baffles me is the sudden oil consumption I was experiencing. I never had to add as much as 1/2 quart in a year before and now I'm adding 1 quart/month. I'm confused.

 

[demarpaint]

Originally Posted By: markhait
They said most trucks that run on synthetics have the most engine problems that they see. Again, I don't believe in too much of what they say, but it has got me thinking though.



I heard those comments before and there is some merit to them. There are people who buy Synthetic Oil under the belief that they can run extended drains with it, and go strictly by the oil companies claims for perfect world use. They don't bother to have the oil tested, and/or completely ignore severe service maint schedules, and just go for it, no matter what. After all it said Synthetic Oil good for up to 1 year or xxxxx amount of miles. Remember these mechanics are not dealing with Bitog oil fanatics they are talking to average people, trying to stretch oil changes when in reality they shouldn't be stretching them.

Good thing your lie worked! Next time follow the OM, and skip extended OCI.

 

[markhait]

I had a GMC Sierra truck before my Silverado and I kept it till I had some 140k miles on it. I did that exact same oil changes on it too. 1 year or just under 25k miles. I NEVER had any problems related to the engine. In fact, its still running as my parents bought it off me and they have almost 200k on it. Why would Amsoil work on it, but not on a Silverado? I drive the EXACT distance now as I did then. Please explain?
PT Barnum also said "There are many freaks, but not enough circuses"!

 

[Pablo]

Originally Posted By: markhait
I had a GMC Sierra truck before my Silverado and I kept it till I had some 140k miles on it. I did that exact same oil changes on it too. 1 year or just under 25k miles. I NEVER had any problems related to the engine. In fact, its still running as my parents bought it off me and they have almost 200k on it. Why would Amsoil work on it, but not on a Silverado? I drive the EXACT distance now as I did then. Please explain?
PT Barnum also said "There are many freaks, but not enough circuses"!


That's maybe why I'm suggesting a Used Oil Analysis (UOA) perhaps this engine has a coolant leak.

 

[tsduke]

UOA is "used oil analysis". Take a sample of your oil and send it to a lab.

 

[markhait]

Originally Posted By: demarpaint
Originally Posted By: markhait
They said most trucks that run on synthetics have the most engine problems that they see. Again, I don't believe in too much of what they say, but it has got me thinking though.



I heard those comments before and there is some merit to them. There are people who buy Synthetic Oil under the belief that they can run extended drains with it, and go strictly by the oil companies claims for perfect world use. They don't bother to have the oil tested, and/or completely ignore severe service maint schedules, and just go for it. Remember these mechanics are not dealing with Bitog oil fanatics they are talking to average people, trying to stretch oil changes when in reality they shouldn't be stretching them.

Good thing your lie worked! Next time follow the OM, and skip extended OCI.

If you look at Amsoil website and what their definition of severe service is, I don't fall under it. As I just mentioned in a earlier post, I had a GMC Sierra and I did exactly the same OCI on it. I sold it at 140k miles and it now is at almost 200k! There was NO engine related problems on this truck.
If extended oil changes don't work, please explain why it apparently worked on one truck, but not the next. My driving habits haven't changed one bit. I still drive the EXACT same distance and even drive the EXACT same route. Explain?
It doesn't make any sense.