Agent 7

I bought a 96 Limited 4 runner about 6 months ago now... and there has always been a slight vibration in the auto tranny when I put my foot hard on the gas (higher rpms). I've searched the forum through and through, but most of the tranny problems in my gen are with the manual tranny.

Anyways has anyone else had this problem? Could it be transmission mounts? Dirty valve body? Any help would be great, thanks!

midiwall

A couple of questions...

1. How many miles are on the truck?
2. Where do you feel the vibration (floorboards, seat, etc)?
3. Any mods to the engine or truck in general?
4. Any (truthful!) history of how the truck had been used before you bought it?
5. 4wd or 2wd?
6. Have you checked the tranny fluid level?
7. Have you REPLACED ALL FLUIDS (oil, tranny, PS, diff's, coolant, washer fluid) because you just don't really know if the previous owner ever had?
8. Does it happen all the time or only when it's cold/warm/hot?
9. What's the range of RPM where you feel this happening (i.e., what's your definition of "high RPMs")?
10. Your profile lists a 98 4Runner as well - any signs of that one doing it?

MTL_4runner

Is it a tranny vibration or an engine miss?
Sometimes fuel starvation or ignition missfire can feel like a vibration at higher RPMs. You should start with the basic maintenance first as Midiwall suggested and this includes (change plugs..OEM only, air and fuel filters, clean the throttle body, change the engine oil, flush the tranny and lube the driveshaft slip/u-joints). Then see if you still have that vibration. I would bet it will be greatly reduced or gone.

Agent 7

Midiwall - 1. 187,000 kms
2. Vibrations come through the floorboards and seat yes
3. There are no mods to the truck at all
4. I bought the truck off a Toyota Dealer on a 1 owner trade in... so I wasn't able to contact the previous owner. All service records were done through toyota, and all recalls, and maintenece were accounted for.
5. 4wd
6. Tranny level is good, but starting to look dirty
7. I replaced all fluids except for the tranny
8. It basically happens the majority of the time... weather doesn't matter
9. it happens in the 4-5000 rpm range
10. lol My profile is a typo... I'll change that now thanks.

MTL_4runner - I have replaced the majority of the fluids already... however I still need to do the tranny... and grease the driveshafts and u-joints which I'll do tommorow. Thanks for the heads up... I'll see how it goes tommorow.

midiwall

Hmmm... yeah, I drive up at 4-5k as well, and get all sorts of interesting things going on!

I think Jamie's got a good idea with greasing everything you can. And if the tranny fluid is starting to look dirty, flush it. And spend the $$$ on a real flush, where they disconnect the tranny cooler and replace ALL of the fluid in there; not just a 3-4 quart drain. Your truck will love you for doing so.

Agent 7

I should also add.... that other than the vibration, it's shifts perfectly fine, and is otherwise in great shape.

Agent 7

midiwall - Thanks... yeah I think I'll get eveything changed (hopefully this weekend, if time permits) and see how it goes. If I'm going to get the full flush, I may even consider adding a tranny cooler at this point to ease the stress on it as much as possible. Thanks for the quick response guys... much appreciated.

GodwinAustin

my taco engine is smooth, then gets pretty rowdy around 3-3500 RPM,and then smooths out again - I think it is because it is in the peak of its powerband at that time/revs and hence the vibrations.

Agent 7

Yeah that could be.. however I think it might be a little more than average. So hopefully with the grease and new tranny fluid I'll be in good shape *fingers crossed*

CCSeniorGuy05

could it be alignment/balance issues?

Agent 7

Pretty sure it's not that..... I had brand new tires put on when I purchased the truck... not only that, but the vibration is very distictive, and doesn't comes through the steering at all. Thanks for the heads up though.

Agent 7

Well just to update.... I ended up greasing all of the u-joints and driveshaft with synthetic grease... and damn, what a difference! It took the majority of the noises, and some of the vibration out. The truck feels really crisp after doing it. I'm still feeling a slight vibration though in the higher rpms, and occationally at idle. If I put the truck in neutral the vibration goes away. This leads me to think it may be a mount of some kind. I re-checked the tranny fluid, and the level was still fine, but just a bit dirty. I'm getting it flushed this friday to see if that helps any. Other than that... anyone have any ideas yet?

midiwall

At this point, I'm tempted to say it's normal. My truck ('96 with 138,000 miles/222,000 km) definitely has vibration fun going on in the upper end.

I can appreciate you being worried, but don't let it become an obsession.

Agent 7

Yeah... I figured it may be normal... and by no means am I even that concerned about it. I just figured I'd see if there was anything I could check without going overboard about it. Thanks again for the help.

4Hummer

U-Joints

Stegall984R

i never floor it and get past 3k.... gas gauge moves to much as it is.

Agent 7

I find this truck to be pretty good on gas, considering I used to drive around an RX-7 with 6 grand in engine upgrades! I was getting about 1/2 tank every 100 kms LOL