problem with overdrive, 2002 SR5 4WD

[johnf]

I have a 2002 4Runner SR5 4WD Automatic Transmission. With the overdrive on, at about 50 mph, the transmission feels like it is slipping. It happens when trying to up-shift or downshift at that speed. I notice it when I am accelerating onto the highway, but when I get past that speed, the transmission will stay engaged in the highest gear. Most noticiable when driving about 50mph, when I accelerate or come up to a small hill, the transmission wont just downshift. It seems to jump back and forth between gears (RPM jumping between about 2500 and 1500).

Engine temp is normal. I had the transmission oil flushed/ replaced one year ago. Occurs with 4WD on or off. No check engine lights are showing. I've had the 4Runner since 2007 and never had any similar issues. I just got on this web site, but it seems like many others have had similar problems with the OD.

Please let me know if you have any advice. Should I have the computer scanned at AutoZone, even though no lights are showing? I'm hoping this is some sort of control problem with the transmission, rather than mechanical. I've seen some of the previous posts mention corroded wires, temperature sensors, or solenoids on the trans. Thanks.

 

[harvickdaman29]

I had a very similar problem after I bought my '98. The trans. fluid had been changed by the dealer before I picked it up so I thought all was well. After reading here about the drain and fill of the trans, fluid in the manual shorts it by almost 2 quarts, I double checked the fluid and it was about a quart low. Filled it to the full line ( or a little above) and problem solved.

 

[johnf]

Thanks. I just checked the fluid after a 30 min drive and it was right between the Hot fill marks. I had the flush and replace done over a year ago, and the fluid looks good. Also, I've been driving with the O/D off, and I've been noticing the transmission slipping when I give it a lot of gas, especially when accelerating on the highway. So it isn't just a problem with the Overdrive, but that is when it is most noticable.

 

[johnf]

possible engine trouble causing "transmission slip" in OD

I have my 4Runner at a shop and they believe my engine is skipping. Mechanic said it would skip when reving the engine with his foot on the brake. The check engine light is not on and no codes come back when the computer is scanned. Has anyone else experienced a problem when in overdrive, which feels like a transmission slip, due to engine trouble?

 

[oceanstate88]

I have the same problem with my 2001, just started two days ago...the battery was dead the other morning and I had to jump start the vehicle. If it isn't low fluid, could it be a weak battery? Is the trans, especially the OD, an electronic lock-up type...I remember a few years back my friend's chevy pick up wouldn't shift properly and it was because the battery was going bad.

 

[brian2sun]

Sounds like the engine is probably missing under load. Change the plugs and wires.

 

[harvickdaman29]

I agree with the others. I had a '00 dodge ram a few years ago with the same problem with the trans shifting erratically. Just before I was ready to junk the truck, someone recommended I check the electrical system, sure enough I had a plug wire not fully on the dist. cap, problem solved. Go figure:redbrick:

 

[YotaFun]

How many miles are on the Truck?
And can you figure out when the manufacturing date is?

Some earlier 02' 4Runners had trans issues where the planetary O/D gear would fail.

My stepdad's 4Runner blew at 100k just my .02

 

[johnf]

Yes, that was it. New Plugs and Wires, and it is running great now.