Question, intermittent hard shift into gear

aeb28

New member
Just recently my 03 4runner (v8, awd) has started shifting pretty hard into drive and/or reverse. I haven't really figured out any kind of pattern, it just seems to happen regardless if engine is hot/cold. It'll happen and then just be totally fine shifting in and out of 'park' for like a day, then clunk hard a couple more times out of the blue. My wife will shoot me a dirty look sometimes and I tell her I promise it wasn't on purpose.

To try and explain the "clunk/hard shift" a little more, it feels a lot like shifting a car out of park with the idle set too high. You get that lurch foward, except RPMs are normal, and it only happens sometimes.

Everything else seems perfectly fine, no CELs, fluid seems fine. I have a KandN drop in filter, but not too much oil and I think I ran seafoam through the intake about 4-5 months ago so I dont -think- MAF sensor is the problem.

Once driving, it shifts through gears seamlessly. It is a daily driver and pulls trailors from time to time but nothing crazy. It is shifing hard enough lately to cause some concern, any ideas?
 
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How many miles on your vehicle and have you had the transmission serviced recently?

Also if you have a K&N filter, I'd make sure the MAF is cleaned and hasn't failed.
 
I understand this thread is old, but as a new user I can't seem to post a new thread myself. If someone happens to stumble upon this and can help me, thank you ahead of time.

Used Seafoam Intake Cleaner, now the transmission hard shifts from 1st to 2nd, a slow late shift. It's gotten worse over the past 100 miles/1 week. I've scoured the internet for what info I can and found that it's a coincidental kickdown cable and/or throttle valve cable going out of adjustment. I can't seem to locate said cable in the 4th gens, which leads me to wonder if it's a sensor in the throttle body and if the intake cleaner fouled up this sensor. I've also read that it can mess up spark plugs, I have not checked any of the spark plugs yet and being the engine performance has only improved, I'm looking back to the device or cable that communicates the engine rpms to the TCM.
 
Your 4th Gen has neither of the two cables you mentioned, so don't waste diagnostic time pursuing them.

I'd start with the transmission basics - when was the last time you completely exchanged the ATF, and what ATF did you use?
 
This would be a good time to get some DeOxit and clean the pins on the white connector on the driver's side of the transmission, just under the gas pedal.

Anytime these transmissions start misbehaving, that's one of the first things you should check, along with fluid. That connector is where the ECM talks to the valve body, and if communication is choked, it improvises.

A while back I had an issue where it would drop into neutral for a split second, then SLAM into second gear. Cleaning the pins took care of that.

The second time, I let a little moisture get in there and it would start out in third occasionally. I figured that out right away though because I was able to manually shift from L-2-Drive, but it wouldn't find 1 or 2 on its own.
 
The first thing to check is the level of your ATF ... sounds like it may be low. In your car that should be dead easy because a '03 will have a tranny dipstick. You could always do a drain & fill. The key is to get the level right and it's a little hard to accurately read that dipstick. But you can do it!





Just recently my 03 4runner (v8, awd) has started shifting pretty hard into drive and/or reverse. I haven't really figured out any kind of pattern, it just seems to happen regardless if engine is hot/cold. It'll happen and then just be totally fine shifting in and out of 'park' for like a day, then clunk hard a couple more times out of the blue. My wife will shoot me a dirty look sometimes and I tell her I promise it wasn't on purpose.

To try and explain the "clunk/hard shift" a little more, it feels a lot like shifting a car out of park with the idle set too high. You get that lurch foward, except RPMs are normal, and it only happens sometimes.

Everything else seems perfectly fine, no CELs, fluid seems fine. I have a KandN drop in filter, but not too much oil and I think I ran seafoam through the intake about 4-5 months ago so I dont -think- MAF sensor is the problem.

Once driving, it shifts through gears seamlessly. It is a daily driver and pulls trailors from time to time but nothing crazy. It is shifing hard enough lately to cause some concern, any ideas?
 
I hate to do shotgun maintenance, but on my 80 series I did the “Rodney flush”? I’ll have to search and get back to you the name and application, but basically you have 2 buckets, one with fresh ATF going to the inlet, and one for old ATF coming out to the old bucket. Using proper hose and fittings. But once the outlet is fresh looking and flowing through the system you should cap everything and the levels should be spot on.
Definitely look up the process and I’ll find the proper name and if it’s a know procedure you can do to these transmissions and post the info. Also, it’s a “shade tree trick”…. Not an FSM procedure.
 
I hate to do shotgun maintenance, but on my 80 series I did the “Rodney flush”? I’ll have to search and get back to you the name and application, but basically you have 2 buckets, one with fresh ATF going to the inlet, and one for old ATF coming out to the old bucket. Using proper hose and fittings. But once the outlet is fresh looking and flowing through the system you should cap everything and the levels should be spot on.
Definitely look up the process and I’ll find the proper name and if it’s a know procedure you can do to these transmissions and post the info. Also, it’s a “shade tree trick”…. Not an FSM procedure.

That works in theory BUT only problem with that method is if you were low to began with then you're still low on ATF, you always need to check the fluid level when servicing any fluids!!
 
Not necessarily, the uptake and output of the fluid isn’t a constant, while servicing it’s not a closed circuit with the dipstick open, and the flow can fill while the output may slow to fill any voids. If it takes more new fluid to fill the system to complete the cycle and flow out as clean red ATF, then the system should be serviced to the proper levels. Also, checking of the atf level is critical when servicing. No advice of any forum should ever be done without further research. I explicitly stated that. Also exclamation point.
 
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Hard shift 1st to 2nd

Anyone have some more input? I’m experiencing the same issue. Hard shift from 1st to 2nd intermittently. Rig only has 150k miles.
 
Anyone have some more input? I’m experiencing the same issue. Hard shift from 1st to 2nd intermittently. Rig only has 150k miles.

First course of action is to properly check the transmission fluid level, if it's good and the fluid has never been changed, changing the fluid would be my next step.
 
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