Possible Emergency - Need Advice ASAP

[keylay31]

Hey guys,
So I just changed my oil for the second time about 3 hours ago at 10K miles, this being the second time I use Mobil 1 fully synth. I did this at my mom's house where all the tools and some of the oil from last time was.

On my drive home (60 miles, mostly highway), I first notice what seems to be a drop in the power of the vehicle, but I'm always a little worried after I do anything to my car. So I start checking my RPM's, and here is what I got:

Park: 700 RPM
Idle: 500 RPM
55mph: 1500 RPM
75mph: 2000 RPM

I seem to remember them about 300-500 RPM's higher than that (with the exception of park).

Ah, and I cleared my computer's MPG thing, and it read approx 27mpg, where I normally read 25ish (instantaneous highway readings).

Did I miss something, forget to do something, mess something up? Am I imagining things? What RPM's do you guys get at those speeds (all calculations were done in Drive).

Note: I'm not so sure about there being less power, but I do feel that the RPM's are a bit low.

Remember, this is a 4wd 2007 v6.

Did I put too much oil in, not enough? Not tighten something enough, sucking air?

I'm quite worried, please help. PS, dont forget to change ur clocks.

 

[keylay31]

Bump. :'( Have to drive to work this morning, hopefully I don't do any more harm to it.

 

[Methodical]

looks good to me.. but ive got an 04 with a different transmission and gear ratios.

 

[CJ3Flyr]

Hey guys,
So I just changed my oil for the second time about 3 hours ago at 10K miles, this being the second time I use Mobil 1 fully synth. I did this at my mom's house where all the tools and some of the oil from last time was.

On my drive home (60 miles, mostly highway), I first notice what seems to be a drop in the power of the vehicle, but I'm always a little worried after I do anything to my car. So I start checking my RPM's, and here is what I got:

Park: 700 RPM
Idle: 500 RPM
55mph: 1500 RPM
75mph: 2000 RPM

I seem to remember them about 300-500 RPM's higher than that (with the exception of park).

Ah, and I cleared my computer's MPG thing, and it read approx 27mpg, where I normally read 25ish (instantaneous highway readings).

Did I miss something, forget to do something, mess something up? Am I imagining things? What RPM's do you guys get at those speeds (all calculations were done in Drive).

Note: I'm not so sure about there being less power, but I do feel that the RPM's are a bit low.

Remember, this is a 4wd 2007 v6.

Did I put too much oil in, not enough? Not tighten something enough, sucking air?

I'm quite worried, please help. PS, dont forget to change ur clocks.

I always notice mine doing a little better on gas, running smoother etc for about 500-1000miles after an oil change. The difference seems greatest if I've done an extended interval (more than 5000 miles). If your oil level is fine, you're fine. Enjoy that sweet, new car feeling! :bigok:

A couple of reasons: The new oil behaves truer to the weight listed on the bottle, 5w-30 or whatever. Second reason (my speculative BS) is that old oil is full of blowby contaminants. The breather feeds into the intake side. Purer air may burn better. Also, the exhaust smells different to the O2 sensors (with old oil breather air) and the computer manages the fuel a bit differently.

Again, correct level, correct viscosity, no leaks and you're fine!!!
:biggrin2:

 

[keylay31]

I slight feeling of a lack of power and the lower RPM's don't worry you? I'm sure 500 RPM isnt kosher... (right?)

 

[CJ3Flyr]

I slight feeling of a lack of power and the lower RPM's don't worry you? I'm sure 500 RPM isnt kosher... (right?)

At certain temps with the A/C and defrost off mine will idle down that low. When it's doing that I wouldn't say it has less power. The tip-in on the initial throttle application is slower... It feels a touch less responsive right off of idle.

You may be right, you may have a problem but I think it's highly unlikely.

A good doctor friend (old guy, since passed) said to me when the sick child is sitting in front of you there's a choice to be made. Treat the mother or the child, either way it'll be fine.

An oil change that's not leaking shouldn't make your vehicle (baby) sick. I'm not slammin' or doubting you; I think it's cool your so into it that you notice all the little stuff. Good Luck :cheers:

 

[simple]

04 v6.

I thought about your thread this morning when I was driving, the only rpm reading I got though was idle, which was 700. My power source on my computer died so I only have the one at work. I'll get the rest of the numbers tonight and post them tomorrow when I go to work.

 

[rook]

I'd relax and not worry about it. If there was a serious performance issue with the engine it would throw a code. Just check your oil levels, but unless you put in over 7qts of oil you will be fine. Engines can also run for a short time being down 2 or 3 quarts.

Your speed relative to rpm's are a function of the gear ratios, so it is impossible for them to change before/after the oil change.

The only thing I can think of is you are having a problem with the torque converter. If it locks prematurely, the engine does not rev up as quickly while accelerating and may explain the loss of power you are experiencing.

 

[keylay31]

The only thing I can think of is you are having a problem with the torque converter. If it locks prematurely, the engine does not rev up as quickly while accelerating and may explain the loss of power you are experiencing.

Any way I could check this, or is a lack of codes enough?

 

[rook]

Any way I could check this, or is a lack of codes enough?

Drive the truck and allow it to reach operating tem. Put it in D and press the brake pedal firmly. Then gently apply the gas while holding the brake pedal down. You should see the rpm's increase by a few hundred. Bear in mind it puts stress on many drivetrain components so don't do it for more than a few seconds. Apply and release the throttle in a gradual manner.

Basically the torque converter allows for some slippage to smooth out accelerating and shifting, along with allowing the engine to rev up slightly on initial acceleration. If you do not see an initial rise of 500-1000 rpm above idle, it may be locking up early.