I have a very well preserved 1994 Chevy z71 truck with 180k. I have owned the truck for the past 6 years and have done all the maintenance myself. I originally started out using Havoline 10w 30 with AC filters but switched to Lucas 15W 40 with AC filters a couple of years ago. I started using the Lucas due to the fact I run it in my Dixie Chopper mower and Bobcat Skidsteer and it seemed like a good oil and Summit has it for a good price. The truck started using a little oil between changes 1 - 1.5 qt the last two times I changed it. I have been using it under a pretty good load towing a 2 - 3k pound trailer working on a rehab house. It doesn't smoke at all and it still runs really well. Does anyone think that changing oil types or grade would help? I realize the motor has considerable age and mileage but I love my truck and want to get the most out of it before I have to rebuild.
1994Chevy Truck 5.7L Oil Question
- Thread starter pondfishr
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I would do 2 things. Go back to 10w30 and completely clean your PCV system and replace the PCV valve then re-evaluate. (but I would use maxlife 10w30 blend)
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Valvoline red-bottle Maxlife 10-30 is what I would use.
It is a great engine and it will love the Maxlife blend, may even help with oil consumption.
It is a great engine and it will love the Maxlife blend, may even help with oil consumption.
Originally Posted By: pondfishr
Sounds good I have used the max life before and always had good results. The Lucas gave me great oil pressure that is one reason I like it but the oil consumption is what I want to try and stop.
Time for a valve-job. I 've done many of the Z-71s with the 5.7 that would start to suck the oil past the guides. All of them had 150,000 or more miles. I also install Ford-style valve seals on them. Chevy's old seal design left much to be desired.
Sounds good I have used the max life before and always had good results. The Lucas gave me great oil pressure that is one reason I like it but the oil consumption is what I want to try and stop.
Time for a valve-job. I 've done many of the Z-71s with the 5.7 that would start to suck the oil past the guides. All of them had 150,000 or more miles. I also install Ford-style valve seals on them. Chevy's old seal design left much to be desired.
Originally Posted By: Mokanic
Originally Posted By: pondfishr
Sounds good I have used the max life before and always had good results. The Lucas gave me great oil pressure that is one reason I like it but the oil consumption is what I want to try and stop.
Time for a valve-job. I 've done many of the Z-71s with the 5.7 that would start to suck the oil past the guides. All of them had 150,000 or more miles. I also install Ford-style valve seals on them. Chevy's old seal design left much to be desired. Th bottom half of the engine is good for about 300K
Originally Posted By: pondfishr
Sounds good I have used the max life before and always had good results. The Lucas gave me great oil pressure that is one reason I like it but the oil consumption is what I want to try and stop.
Time for a valve-job. I 've done many of the Z-71s with the 5.7 that would start to suck the oil past the guides. All of them had 150,000 or more miles. I also install Ford-style valve seals on them. Chevy's old seal design left much to be desired. Th bottom half of the engine is good for about 300K
Yes, pull your spark plugs. Whichever cylinder is sucking the worse will show alot of white ash deposits. Eventually, i've seen them get so back that that paticular cylinder will quit firing.
No. The bottom end of these engines will get it done for at least 300K if the are serviced. I would do the heads(if that's the problem)and leave the bottom end alone. Sounds like you have kept the truck serviced well so a valve job is all that will be needed. Maybe a t-chain if it has not had one. Thats it.
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