Switched to Mobil1 0w30 today

[GasSavers_GasUser]

Originally Posted by Jay2TheRescue

Yes, I do mean on the original engine & transmission... Modern automatics last a very long time if maintained properly.
-Jay

Yes, maintenance is the key in addition to not abusing the vehicle. My GMC truck with the original tranny/drivetrain is still going strong and just turned 200,000 miles. It also served as a tow vehicle. I bought it new and did all the routine maintenance and my Son is still driving it.

As to the 0w30 oil, I was thinking of trying it but leary of the 0w being too thin. The manual recomends 5w30 on mine and I am running that weight in Valvoline syn.

Both the 0w20 and 0w30 weight syn oils are recomended on many of the newer vehicles though, but I don't know if the engines were modified by the mfg in any way to run the 0w oils. Although I do think it is recomended for better fuel economy in the instances where the mfg recomends it.

So I am curious how you make out using it where your recomended weight is probably 5w30 on your truck.

[theholycow]

Originally Posted by GasUser

My GMC truck with the original tranny/drivetrain is still going strong and just turned 200,000 miles. It also served as a tow vehicle. I bought it new and did all the routine maintenance and my Son is still driving it.

I'll echo that for another data point. 180,000 miles here, quite a few towing slightly beyond my GCWR up steep mountains on hot August days. The 4L60E is said to be weak and breakage prone compared to other GM automatics, too.

[Jay2TheRescue]

Well, its only been a couple of days since the oil change so I don't have any fuel usage data to report. The engine does run very quiet and smooth, but then it did anyway. One thing that is starting to scare me though. Remember earlier that I mentioned the vibrating pedal @ light throttle at certain speeds? I've done some talking with my brother in law (The service guy from Ford) and we've come to the conclusion that my torque converter is probably going bad. The tough part is that I won't have time to take it in and get looked at until next week. At least I don't drive far, and when I feel the pedal vibrate I just hurry up and get out of the range where its vibrating.

I want to get this fixed before I'm buying a new transmission. Not really money in the budget for that, especially since I just bought $800 worth of tires & alignment recently, & I replaced the fuel pump this summer.

Of course this is putting a damper on my travel plans. I had plans to make trips to Florida and Long Island before the end of the year.

AAMCO advertises that they specialize in diagnosing transmission problems and being able to save you money by not replacing the tranny when its not required. Has anyone here had experience with them good/bad/indifferent?

-Jay

[theholycow]

Ah, bummer. What's the technical explanation for how a failing torque converter causes pedal vibration? Maybe the TC is quickly oscillating between locked and unlocked, which is oscillating the engine on its mounts, which is then being transmitted through the throttle cable?

Why not drive the BWH and Rusty until you can get it looked at?

[Jay2TheRescue]

Well, I'm in the middle of my workweek right now. I work from 6:45 am to 8:45 pm. Rusty is currently ~70 miles away in my parent's driveway with about 3/4 ton of gravel in the back. The BWH is at my old house still (I'm not completely moved out yet), and I don't have the capability to drive out to the house and drive both vehicles back. I may try to get one of my employees to drive me out there later today, but being a saturday we're going to be busy today. Might not have time to get it done.

-Jay

EDIT: I forgot to discuss why. I don't really know why. Its most pronounced @ 40 - 42 MPH with the pedal depressed about an inch. We're thinking the TC clutch is on its way out. I'm hoping to get it to a transmission shop and confirm that before I go any further. If so, a new TC, flush the fluid & I'm good to go. I want it fixed before I'm buying a new tranny. I really don't have the funds for a new tranny or a new truck right now.

-Jay

[Jay2TheRescue]

I just came from a few errands. I decided to drive in "3" instead of "D". The pedal hardly vibrated at all. I think I will keep it out of 4th gear until I get this looked at.

[shatto]

Story #1.
I used to have a Sonoma.
On the theory that "if a little is good, more must be better" I ran Castrol 50 weight oil.
Then I discovered Amsoil, and was told that heavier than specified oil actually reduced lubrication in some cases, like a cooling spray onto the piston bottom.
Oh.
I switched to Amsoil 0-W30 and got an immediate 3 MPG improvement.

Story #2.
I drove a Dakota.
It came from the factory with synthetic engine oil, and so, never showed any change in MPG when I began using Amsoil 0-W30 motor oil.
The better oil did, however allow the original engine and transmission to last the entire time I had the truck. 623,000 miles.

Story #3.
The Dakota had a mildly annoying surge, on cruise, which matched the torque converter locking and un-locking.
3 dealers and two major transmission franchise shops said I needed a new transmission.
The lab tech at Amsoil's Oil Analyzers told me there was not only no sign of any transmission wear, it actually had less than could be expected.
Because I'm cheap and diagnosis was hundreds of dollars, I lived with it. I later, as in around 300K miles later, discovered the problem was a faulty throttle position sensor.
Moral of the story; Be careful getting advise from someone who can sell you a transmission.

[guest001]

Originally Posted by Jay2TheRescue

I came back from an errand just now and only noticed the vibrating pedal once. There really wasn't a noise associated with it. When I got back to my office I left it running and I looked under the hood. The truck was pretty quiet before, but now the sound of air moving from the fan is definately louder than the engine itself. I think this could be super quiet if I switched to an electric fan. I tried lightly revving the engine by activating the throttle directly on the intake manifold, but I sensed no vibration, and heard no objectionable sounds. Maybe the throttle cable is getting snagged on something as it goes through the firewall. I find it very hard to believe that any perceptable vibration could be transmitted through the throttle cable to the pedal. I must somehow be sensing the cable going through a kink or rough spot right at that point. I'll look into it more later I figure if something was vibrating that badly that I notice the pedal vibrating there should be some sound or the whole truck would shake so badly that I wouldn't notice the pedal vibrating.

-Jay

are all your grounds there, clean and tight?



would love to see any data on improvements from the oil change.

[Jay2TheRescue]

At this point I think any improvements may be tainted by transmission repairs... I first noticed the vibrating pedal a few hours after the oil change. I even thought maybe they topped off the transmission with the wrong type of fluid, but I checked the ticket and they marked the tranny as full, not needing any fluid. When I pulled the dipstick yesterday it was at the "add 1 pint HOT" mark. This should not make any perceptible difference in operation. I would add 1 pint, but I don't have any Dextron III fluid on hand at the moment. The fluid should not be worn out, I just had the tranny flushed 6 months ago (less than 10,000 miles).

-Jay

[shatto]

Originally Posted by Jay2TheRescue

At this point I think any improvements may be tainted by transmission repairs... I first noticed the vibrating pedal a few hours after the oil change. I even thought maybe they topped off the transmission with the wrong type of fluid, but I checked the ticket and they marked the tranny as full, not needing any fluid. When I pulled the dipstick yesterday it was at the "add 1 pint HOT" mark. This should not make any perceptible difference in operation. I would add 1 pint, but I don't have any Dextron III fluid on hand at the moment. The fluid should not be worn out, I just had the tranny flushed 6 months ago (less than 10,000 miles).

-Jay

"I first noticed the vibrating pedal a few hours after the oil change."
And.....what did we learn from this?