synthetic oil Vs. Castrol GTX high milage

[4.0Rerolpxe]

which is better for higher milage vehicals my x has 160,000. is there a difference in hp, or mpg?

 

[ghoster]

its really depends..i mean if u have never used synthetic oil in that truck..i wouldn't suggest using it now. YEs its better than regular oil but it also might clean up where theres oil build up and possibly cause an oil leak.
Personally i would go w/ high mileage oil. My old truck had 90k miles and i really wanted to use synthetic but just used gtx hig mileage and never had any problems

 

[4.0Rerolpxe]

good point, wouldn't want to go poking holes in my motor

 

[ghoster]

good point, wouldn't want to go poking holes in my motor

exactly

 

[4.0Rerolpxe]

thx

 

[daveydavido]

i also was undecided about that but seeing as mine has 150k i went with the castrol, so far so good, i did my oil change the day after i bought the truck after i ran seafoam through everyway possible so i couldnt tell you if there was a dif in mileage or anything. nice and smooth though

 

[Nocturnall]

its really depends..i mean if u have never used synthetic oil in that truck..i wouldn't suggest using it now. YEs its better than regular oil but it also might clean up where theres oil build up and possibly cause an oil leak.
Personally i would go w/ high mileage oil. My old truck had 90k miles and i really wanted to use synthetic but just used gtx hig mileage and never had any problems

What? Have you experienced this personally RECENTLY?

Use synthetic your not going to see any new leaks, that's something that happened when synthetic first came out. I switched at 115k, many many MANY people on this board have switched at over 150k, some at 200k and have had no problems. Synthetic is better for the motor, isn't effected by cold like dino oil, it's just a better oil to use. Amsoil, Royal Purple are some of the better or best to use. Mobil One and the others are alright but not suggested for extended use. Search this site and you'll see this topic has been covered as much if not more then the "How do I lift my explorer" topic.

Plus if for some really really far out weird reason the synthetic caused a leak, do you really want to hide the worn out seal by using an oil that will cover up the failing seal or know about it so you can fix it before the seal totally fails and your in the middle of no where leaking oil faster then you can add it?

 

[Willard]

Actually, I switched over around 200k, and it did start leaking more.

However, keep in mind it already did (minor), it just made it leak worse. I knew this already, and it doesn't bother me, just a good excuse to replace the rear main seal. This is the one seal that started leaking, however, the rest are fine.

 

[snoborder42]

I've been using the GTX high mileage stuff for about 2 years now. It got rid of that annoying lifter tick on start up and the tick as also much quieter at idle and speed than when I used other oils.

I like many others used a synthetic blend once, it made my oil leak 10x worse. I had a very small valve cover leak and once I used that oil it became much much worse. To the point where I was losing about 1 qt of oil every 3000k miles. It may have been a complete coincidence but that was my experience with synthetics and that was with about 125k on the motor...

 

[pugsy]

I use Castrol GTX High Mileage, and still get valve/lifter ticking when it's cold. I've got 250K Km's on the engine.
I'm with the others though and not chancing opening up a leak with synthetic. I'm down about 1 quart every few thousand KM's anyhow, but nothing leaking to the ground - I'm assuming it's just comsuption from the old engine. Synthetic would help burn off however, but not interested in the extra $$ for such an old engine.
My new truck however, I've used synthetic since I've had it, so it's worth keeping it on the stuff.

 

[4.0Rerolpxe]

mine ticks on idle and startup, and i've been using castrol GTX for a few months, i've run seafoam trough the vaccum lines, and in the gas tank. any ideas on fixing ticks. wouldn't want my truck to get lyme disease lol

 

[4.0Rerolpxe]

it ticks even when its not even cold out

 

[aldive]

its really depends..i mean if u have never used synthetic oil in that truck..i wouldn't suggest using it now. YEs its better than regular oil but it also might clean up where theres oil build up and possibly cause an oil leak.

If the motor is not leaking currently, using synthetic oil is not going to cause it to start leaking.

 

[aldive]

I like many others used a synthetic blend once, it made my oil leak 10x worse. .

Ah, another blaming "synthetics" for leaking.

This example holds no water, the amount of synthetic oil in a blend is very small ( actually there is no requirement for a particulate percentage - if it contains just one drop, it can be called a synthetic blend ).

 

[Nocturnall]

And if a leak started I would think it's time to change that gasket since it's obviously failing, not time to put an oil in that will hide your weak points in the motor.

 

[aldive]

And if a leak started I would think it's time to change that gasket since it's obviously failing, not time to put an oil in that will hide your weak points in the motor.

Sage advise. Don't blame the oil for your poor maintenance practices.

 

[briwayjones]

Amsoil, Royal Purple are some of the better or best to use. Mobil One and the others are alright but not suggested for extended use.

I have seen no problem using Mobil 1 for extended use 10,000-12,000 miles determined by oil analysis. And that is regular Mobil 1 not Extended Performance Mobil 1.

 

[protomind]

Hmm I was bout to pose this same question in this forum. I have a 94 with 85k on it and do not know if I should use the castrol or mobil 1 still. I have no oil leaks that I know of.

 

[aldive]

Hmm I was bout to pose this same question in this forum. I have a 94 with 85k on it and do not know if I should use the castrol or mobil 1 still. I have no oil leaks that I know of.

Use synthetic if you have no leaks.

 

[JDraper]

Synthetics will ALWAYS outperform non-synthetics. Period! I run synthetic in just about everything, including my lawnmowers, rototiller, etc. You don't get viscosity breakdown like you do with conventional oils, so they protect the motors better over the long haul.