Accepted Answer

I seen this problem one time before. Oil changes were done every 10,000kms instead of every 5,000kms and they waited too long between the oil change intervals( more than 3 months). It was probably a good idea they changed all the lifters just to be safe, if one or two is clogged then there is a chance all of them could have been or will be. GM recommends an oil that is 5w30 viscosity and meeting GM Standard GM6094M. Also oil changes must be done more regularly if: Most trips are less than 5 miles (8 km),Most trips include extensive idling, such as frequent driving in stop-and-go traffic,You frequently use a carrier on top of your vehicle,The vehicle is used for delivery service, police, taxi, or other commercial application. I also have seen people run one liter of transmission fluid, (instead of engine oil... i.e 4 liters of oil and one of transmission) in yor vehicle for a couple of kilometers then drain it and refill with new oil. Transmission fluid has good detergent properties. I hope this answers your question.

Expert:	Technician66
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Accepts:
Answered:	5/1/2008

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