crazy question i guess but thinking about running Lucas! but will i see that big of a life difference between a lower mile truck and mine with 200k on it? Is it wise to run a synth now?
Or will it hurt it? help it?

 

I think the only real disadvantage to running synthetic now would be oil leaks. Everycar I ever used synthetic in always leaked oil like a sive.

 

I asked the "will syn leak in truck that had regular oil before" question on this forum, requesting only personal experiences, not "the brother of my former girlfriend's cousin told me". All who replied said, did not have a bit of a problem with leaks. Looks to me that this issue is the thing of the past when the rubber compounds were not as good as today and seals were getting hardened sooner.

 

Any good quality oil will give great service that meets current service standards and is changed regurally. Syn oils will probablly go longer between oil changes. Must have oil analysis on extended changes to assure still good.
My oil was still good at 20000 miles. Thought that was long enough for me.
Have heard far to many claims that such & such oil "made my engine last XXXK miles." Well, I guess it gives bragging rights, but doesn't prove much.
Total preventive service is important part of long life of any unit.
Remember who is a direct beneficary of some high priced oils sold by individuals/salesmen.

 

Amsoil has told me that you can expect more leaks on higher mileage vehicals. I think it is even on the website. My truck has gone 260,000 mi on straight 15-40 Rotella. Why change now. Maybe when I get my 04-05 CTD, I'll run it in there. But to answer you question, I have not run Synth. So I can not say about leaks,

But my brothers girlfriend, who knows a guy, who's mom, sisters, bestfriends, neighbor from Highschool, said that they had leaks. Just had to add that. LOL

 

I have no new leaks in mine since changing over 1 year a go.

 

When I bought my truck it had 130k on the clock, the previous owner ran dino oil only, I switched the 0w40 synthetic right after I bought it and no problems...

 

Switched to Rotella T Syn at 120,000 miles and do not have any leaks.....Changed from Regular Rotella T.

Change oil & filter every 5,000 miles. Has 155,000 miles on it now.

 

I switched to synthetic on my 97 Tahoe and it leaked at the rear seal for about two weeks and then stopped. I haven't had any leaks since. This was about two years ago and I switched because it hit 100,000 miles and I wanted to do all I could to help engine life because I reallly love this vehicle. I haven't switched the Cummins over yet mainly becasue of cost. I can change the oil for less than 30 bucks. I intend to switch to synthetic and oil analysis eventually though. Kurt

 

I'd definitely consider a synthetic, but Lucas would be near the bottom of the list. I distrust brands that seem to rely so heavily on advertising.

It's almost like they are the anti-Shaeffer's, which has survived solely on reputation, not on massive marketing budgets.

I'd love to see a lab test done on most of the Lucas products-- I suspect they would not live up to the hype.

JMO

 

I switched from Rotella dino to Amsoil at 176K miles and have no leaks at all.
It's been 2900 miles since the change.

 

Only thing I know is Rotella (Dino) STINKS! I mean, literally stinks. When I shut my truck off and walk around the front, it smells like burning sweat socks. It has dissipated now, after about 5000 miles.

I'm going to try Delo the next oil change. Synthetic is out of my price range, and I had a negative experience with it in a Mustang a few years ago. Dino oil with 5000 mile change intervals for me.

 

I had switched to amsoil at 12k and at 120k I had some leaks. Not big leaks but anoying little ones. The worse one was from the vacuum pump seal. At 120k, I switched back to dino oil,(after reading test results on another forum.) Now I use valvoline premium blue (cummins recomended grade), and after 20k more miles[I now have 140k] the leaks have all stopped. This might be a fluke, but I'm happy and for my money thats all that matters to me.

 

Hohn, have you seen the test they did on Bobistheoilguy.com with the gear and engine oils? they had a box with 2 seperate chambers with gears in them, all driven by the same electric motor. they tested the oils against schaeffer products, then added Lucas Oil Stabalizer to the brand x products. Once the lucas was added, it actually made the brand x stuff foam up and arriate like mad at higher speeds!
Don't know if this was really any way to test the stuff, but I know I'll never run it in my vehicles.
I've also seen some posts from guys that did a virgin oil analysis of their oil with lucas mixed in, and it did little to the oil other than thicken it a bit.

 

Amsoil has a gear oil white paper out now, Lucas has to start out very high with addatives to meet viscosity and it falls out of range very fast.. not the best gear oil.. never tired their Engine oils.. THough amsoil 5-30 has been great to me,