Switching Conventional Oil to Synthetic Oil

[BlitzKeg]

I am thinking about switching my conventional oil to synthetic oil.

I'm using Quaker State High Mileage 10W30, I want to go with Royal Purple High Performance 10W30.

I drive a 2000 4x4 4.3 V6 with 180,000 miles with no aftermarket mods.

I live in Dallas/Fort Worth, Texas. Temperatures very 103F in the summer and 20F in the winter.

Is that a good oil weight?
Is there any precautions I should take when switching conventional to synthetic?

I am not going to change anything until I get some feedback. I trust you guys. I love this Forum.
I also have been underestimating the potential of my blazer. I do plan to start modding it for more horsesys. Then I will stop calling them horsesys.

[b1lk1]

There is no harm from switching to synthetics and then back and forth. I would run 5W30 in my truck (which I do, Mobile 1 5W30 to be exact).

As for adding performance, do a full compression test and be ready to need to freshen things up first. These are good motors but their shelf life at stock performance is about 250,000 miles.

[toddman67]

I think you should visit www.machinerylubrication.com and look up the articles that talk about synthectic and conventional oils. These articles describe pros and cons which are different for each of us and our driving habits ETC.
You need to base your decision for your application.
Some guys have no problems switching, however others contradict these actions based on bad experiences.
Personally I would'nt change this late in the game and would stick with what has worked for years, but this is just my opinion.

[BlitzKeg]

Yea, I agree. I think I just got caught up in all the hype with more power with something as easy as an oil change. I feel like a dimwitted consumer. Damn late night commercials.

I really think the power difference would probable have 1 or less hp deviation.
Thank god for the internet.

I have had a compression gauge for the past 15 months and haven't used it yet. Great idea. I think I should focus on upkeep and preventative maintenance then performance with such high miles.

[4x4 blazerguy]

Originally Posted by toddman67

I think you should visit www.machinerylubrication.com and look up the articles that talk about synthectic and conventional oils. These articles describe pros and cons which are different for each of us and our driving habits ETC.
You need to base your decision for your application.
Some guys have no problems switching, however others contradict these actions based on bad experiences.
Personally I would'nt change this late in the game and would stick with what has worked for years, but this is just my opinion.

Thanks for the link to Machinery lubrication. They offer a lot of great info. I personally have switched my SUVs to Synthetic motor oil. I run 15-50 in both. Does it work better who knows. What I do know is our Blazer 4x4 when bought used had 87,000 miles & at 89,000 developed an engine knock (piston slap). I switched to synthetic oil & the engine now has 117,000 miles & the knock isn't any worse oil pressure remains the same & fuel mileage is 18-22 MPG. To me I buy Napa oils & mineral oil is about $3 & synthetic is $4.39. I extended my oil changes from 5000 miles to 7500 miles. So I find synthetics to be a little more cost effective. Our other SUV is a 98 Jeep Grand Cherokee Limited 5.9 with 123,000 miles.
But I agree with those that say leave it as it is. 180,000 miles is a lot of miles. If mineral oil got you there then stay with it. The best of your truck is used up IMHO. I have run vehicles to 300,000 but I had to do a lot of rebuilding of parts to get that. If it was a Toyota, Honda that would be different. I'm a retired mechanic.

[4x4chevymanS10]

i just switched from penzoil 10w30 to amsoil 10w30 you only need to change the oil every 25k miles and the filer after 12.5k well worth it costing only about 60 dollars.
been running it for about 10k now and no poor results oils still clean and the thickness it should be at.
hope it helps

[91goldbomb]

saying that harm will be done by switching from conventional to synthetic and viseversa is a myth. if you think about this, they have semi synthetic oil. wich is part sythetic and part conventional. so if you can have both in there at the same time how could it effect anything by having either or? as for goin 25k on an oil change, i dont care how good the oil is id never go that long. but if you use synthetic, it does give you a bit more performance and fuel mileage due to less friction. the only harm it would do by switching to conventional is loosing the benefits of the synthetic. most newer gms call for 5w30 except some 3.8s wich call foe 10w30 all tho it does all depend on the climate and temp of the location. i personally use 5w30 valvoline high mileage (maxlife) semi synthetic, and it works great for me