Transmission shifting / slipping under load

[jmcguirefl]

Has anyone had a problem with their Tundra slipping while under acceleration.. i.e. like getting on the freeway onramp. I have never had a problem but noticed today after stopping at a toll booth and then accelerating away, that under hard acceleration it slips. Still accelerating, but a stuttering/stumbling feeling. Under easy normal take off like in town it is fine. But hard launch, or passing on the freeway causes the problem.

I got home and was hoping I was low on tranny fluid, but it is fine and clean. Now I don’t know where to look.

Thanks,

2000 Tundra 4X4 Limited original owner
129k

[mstever]

Get your tranny checked...My 2000 V8 Access Cab (157000km) just blew the ATF cooler in the rad and possibly ruined the transmission in the process. From my investigation there are many TS users with 00-02 model Tundras that have had transmission problems...

Personnal advice...sell while it's still worth something.

Matt

[Hi Volt]

Is the slippage constant or is it momentary during the shift, kind of like a flare ?

Have you or a shop put any additives into the tranny ? There are a number of additives out there that can cause issues because they impregnate the clutches. The simple fix is to get a tranny flush and the problem will diminish after a couple of hundred kms.

Another possibility you may have a shortage oil flow through the filter screen. The simplest would be to again get a tranny flush, it will usually dislodge any large blockages and ease the problem.

A third cause can be the throttle body ! Clean the throttle bore thoroughly with a spray cleaner. There are small air bleeds that are used for idle, when clogged they cause the throttle control motor to re-adjust which changes the TPS sensor position. This sensor also controls transmission shifting and line pressure ( ever notice that the transmission shift softly under light throttle and firmly under heavy throttle ?) the ECM alters transmission shifting from this sensor. Before spending alot of money I would get the flush and clean the throttle bore. ( note: the engine will be hard to start after the throttle cleaning, so hold the pedal to the floor and start like it was flooded, then keep the revs up until the engine runs smoothly and idles on it's own ).

Hope this helps

[Cian]

Hi Volt -

This is very good info, but I'm a newby at all this but I learn quick.

So "throttle body cleaner" is simply a spray cleaner I can get at the local auto supply, right?

Now how does one get access to the throttle body?

To be honest, I have no idea even where to start looking.

[Hi Volt]

Yes the cleaner is available at the auto parts store, it is basically carb cleaner although usually called something like "Intake and Throttle Body Cleaner". Warm up the engine beforehand and leave it parked outside or at least where the exhaust is outside as it will smoke quite a bit after the cleaning for a minute or so. Shut the engine off and grab a 10mm socket. To gain access to the throttle body, remove the black metal decorative cover (says "4.7L" ) held on with 2 - 10mm acorn nuts. Below that you will see the large black plastic intake hose held on with a hose clamp. Loosen the clamp and pull back the hose. For more working room you can also remove the 6mm bolt the clamps the rubber AC hose onto the intake hose. Place a wad of paper towels under the throttle opening to absorb any spilled cleaner. Hold open the butterfly ( brass disc inside throttle ) and spray the cleaner all around, especially concentrating on the upper inside of the throttle bore. Be careful to keep the cleaner off painted surfaces and away from your eyes, a pair of disposable gloves will help keep your hands clean. Expect a fair amount of black residue to wash back out of the throttle bore onto the paper towels, but keep spraying until it all looks clean. Re-attach the intake hose ( also the AC hose clamp if removed ) and install the metal cover. Start your engine like it is flooded ( it will be ), so hold the pedal to the floor while cranking until it catches. You will have to keep on the throttle until the engine will idle by itself so play with the gas as necessary. Over the next 30 seconds or so, rev the engine a few times to 3500 - 4000 rpm. The exhaust will smoke as the cleaner burns off in the engine. Take the truck for a drive. The idle could be high for a while until the computer re-learns the position, all depends on how dirty the throttle was.


It also would not hurt to clean your mass air flow sensor as well, but do it after the throttle service is complete along with a drive. Again there is special "Mass Air Flow Cleaner" available. Your mass air flow is located on top of your airbox held on with 2 phillips screws. With the engine off, unplug the 5 wire connector and remove the sensor. CAREFULLY spray the fine wires you see inside. Spray all around inside, but do not touch the wires. After the cleaner evaporates, re-install the sensor and plug back in ( listen for click on the connector ). Start your engine and take for a spin.

[Cian]

Thanks Volt!

I really appreciate you taking the time.

This is new to me, but it sounds pretty straight forward.

You ROCK!

[Hi Volt]

Thanks man, good luck.