08 Jeep 3.8L

Joined
Nov 9, 2018
Messages
59
Location
Lake Jackson Tx
Have been thinking about switching over to Valvoline VR1 10w-30 in my Jeep. I know it doesn't have a flat tappet cam but, being a overhead valve pushrod would it benefit from a higher ZDDP?
 
Not a single benefit, you'll just be spending extra money on a niche product that's not necessary or advisable for your application. Aren't these engines kind of infamous for oil consumption too, putting a high phosphorous oil in an engine known for burning oil is probably not a good idea.
 
I bought a new 2010 Jeep Wrangler with the 3.8L. Kept it fours and it never burned a drop of oil. I got rid of it because the 3.8l was such a gutless engine I couldn't take it anymore.
 
Even most flat tappet cam engines won't benefit from ZDDP. The 4.0L jeep guys fall all over themselves over it, but unless there's a metallurgy issue with the camshaft, they don't have enough valvespring pressure to wipe a lobe anyway.
 
Not a single benefit, you'll just be spending extra money on a niche product that's not necessary or advisable for your application. Aren't these engines kind of infamous for oil consumption too, putting a high phosphorous oil in an engine known for burning oil is probably not a good idea.
+1

These engines usually burn a decent amount of oil, the only thing more ZDDP might do is kill the cat converters.
 
I just wouldn't spend extra but if your engine hardly or hopefully doesn't burn any oil feel free to use any ck-4 diesel oil with the ford wss spec since it's bound to have 1k ppm in ph and zn and they're well priced with great performance.

Many of them are syn blend but don't say it on the bottle. Some home depots still sell castrol gtx diesel for the old price of 10.97 a gallon which is good. Supertech diesel is also great but a bit more now.

What oil do you currently use and what's your consumption if any. if it burns a quart every 2k with a 5w-30 i'd just suggest a gasoline 10w-40 instead. The Zn would poison the cat faster.
 
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I had my 08 JKU for over 10 years and 100K miles. It was underpowered but always got me where I wanted to go. I ran a 5w-30 synthetic and changed it every 5K miles. It still ran good when I had an LS conversion done.

Toward the end it would go through a qt of oil about every 4-5K miles.
 
I don't consume much oil at all. It's less than a half a quart at 3k when I change the oil. I was just wondering if a higher ZDDP would benefit it. I had a 4.0L and it would tick especially when hot out and running the VR1 made it much quieter and it ran smoother.
 
I don't consume much oil at all. It's less than a half a quart at 3k when I change the oil. I was just wondering if a higher ZDDP would benefit it. I had a 4.0L and it would tick especially when hot out and running the VR1 made it much quieter and it ran smoother.
I'd run whatever 5w20 or even 5w30 synthetic that you can get for a decent deal. The 3.8 is a tough engine that is just hard to kill. I've seen a good number of them well past 200k and some with over 300k, running well and reliably. You've got a good one, if it burns that little amount of oil.

Mine sometimes burns about 3/4 quart per 1k miles and sometimes burns none. It's got 166k on it now and has done that since probably 40k. But it runs like new. I change plugs every 40-50k and have changed plug wires twice. It has a new water pump, as well. The first one went about 150k before it began to leak a little. I've got a lifetime warranty so I just take good care of it, feed it good oil every 6k miles, and drive it. It's never left me stranded. I've mostly run Mobil 1 5w20 with a few runs of other oils and weights. But it does just as well on the vanilla M1 5w20 as anything.

It's cheap to maintain, too. I just swapped the timing belt, tensioner, and idler pully. I used a Gates kit that was about $100 and it took me 10 minutes. It's so easy to work on this engine!

As for the power, it ain't great, but mine has the six speed with 4.10 gearing and 33" tires and isn't too bad. It tows my fishing boat and a camper pretty well, too. It's a beast off-road and has tackled everything from Moab to Windrock to Kentucky to Maine and everywhere in between. Love that old Jeep!

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