will 10w-30 ruin the timing on 4.0 sohc?

[biggiesize]

I am considering using 10-w30 because I have the opportunity to get a heck of a deal in bulk drums,but......I know that 5w-30 is a thinner oil that does better for startup lubrication on the SOHC timing tensioner.What are some of you guys thoughts on this?Anyone run 10-w30 in their SOHC for years with no timing problems?I have always used 5-w30 and at 190,000 miles,I have absolutely no timing rattle,and I dont want to cause issues with that just to save a little money on oil.

 

[shadowless127]

at 190K miles, why in God's name would you even consider changing something when everything is working nicely? Please don't say to save money, because that's just a recipe for disaster.

 

[2000StreetRod]

stable ambient temperature range

One table I have lists the stable ambient temperature range for SAE 10W/30 as -4 deg F to 104 deg F. How cold does it get in Virginia in the winter? If it gets below -4 then you're just asking for trouble.

 

[biggiesize]

our winter nights avg. from 20-32.I would definitely run 5w-30 in it during the winter,but I am thinking of the summer startups.How much quicker would 5w30 start to lubricate over 10w-30?Is it a matter of seconds or is it milliseconds?

 

[BubbaFL]

Personally I believe the SOHC timing components need heavier oil than the 5W-30 Ford says to use.

Heavier oil means more oil pressure, which should increase the force the hydraulic tensioners exert on the cam chains. This is probably why STP oil treatment quiets the cam chain rattle.

This is probably also the reason Ford didn't back-spec the 4.0 SOHC to 5W-20 like they did almost everything else.

Having said that - if you have 190k on the original timing components, stick with what you're doing!!!

 

[2000StreetRod]

chain slip & oil pressure

It's my opinion that timing chain slip is most likely to occur at engine start when there is no oil pressure to the hydraulic tensioners (the spring in the hydraulic tensioner is too weak) or during engine rapid deceleration. Low viscosity oil reduces the time for the hydraulic tensioners to exert force on the guides at engine start. Members that use synthetic oil don't seem to be experiencing sooner chain slip than members using higher viscosity conventional oil.

 

[JDraper]

Here are some interesting comments on oil weights from one of the mod motor engineers. Now he is talking about the V-8 mod motors, but it's interesting reading. If you click on the link, pay attention to the posts by swhiteh3. http://corner-carvers.com/forums/showthread.php?t=36607

 

[mistertonylee]

I've run 10W30 for a few years (since I owned it) with absolutely no problems. I live in the NC mountains, where we get down to about 0 deg. F a couple of times a year.

 

[oguzma0679]

The guys at autozone always suggest 10w30 for me when its time to do my oil change,I'm @ 140k , I get a loud rattling noise about twice a day when I start it up and it won't go away sometimes. Did the oil cause that problem? I live 2 hours east of L.A. so its usually hot here, I'd say triple digits from may to sept. Ive owned two 97 xlt's and they both made the rattling noise

 

[SoNic67]

At the cold start you have no oil in the engine.
10W will be thiker than 5W and takes more time to be pumped there in suficient quantities. Matter of seconds difference. Every time you start you rub the bearings metal-on-metal and pistons are slaping the rods against crankshaft with no lubrication in between. That's the noise you hear, deep in the engine.

Is not worth it. Good syntetic oil lasts 10000 miles or a year whatever comes first. How much are you saving with a bulk oil that need to be changed at 3000 miles (add the oil filter there too).

 

[2000StreetRod]

Almost 3 seconds

With my Accusump pre-oiler it takes almost three seconds from the time the ignition is switched On until the oil pressure indicator jumps to mid-range (about 5 psi). I don't start the engine until I have oil pressure. I installed the pre-oiler mainly to extend the life of the camshaft timing components but a good pre-oiler probably doubles useful bearing life.