power issue or transmission issue
 

its an 89 4runner auto trans, 4x4 sr5 3.0 v6 if this helps specify.

I only experience power loss issue or a transmission issue going up long steep hills (hwy 50 towards Tahoe)

Once the climb started to get pretty steep the 4runner started shifting funny. It was almost like it didnt want to stay in the proper gear to get the correct power so I would be bogged down (around 1.5k rpm) or almost redlining. When it would stay in the bogged gear, I could not go faster than 35 mph (even with gas pedal almost floored. If I pushed any further down on the pedal it would drop down a gear and almost redline. Occasionally it would be in the correct gear but for the most part it was constantly shifting (no hard jerks) just had no idea what gear it needed to be in.

On the way home (2 days later) I was hoping the transmission might have just been hot and was acting up, for the most part it wasn't as bad coming home (although I took a different route and was going downhill most of the way) I put it in 4hi to get out of the basin so that the front could maybe help take some pressure off the back axle but at times was still unsure what it wanted and was back to 35-40mph.

When I got home I tried to research this online and havent found any definitive answers. It appears it would either be the trans, a solenoid or fuel pump/filter. The last 30-45 min home was back on sacramento's fairly even freeways and had no problems shifting through the gears which makes me think that it isnt just the transmission going out. I have had an 89 jeep cherokee that I needed to replace the fuel pump on (the jeep would just die and need to be started again) and the 4runner isnt showing any of those symptoms so I dont believe it is the fuel pump. There are 270k on it so maybe worn down gears? the motor was replaced but idk about the tranny.

Any help or advice would be much appreciated.

Welcome to the forums!

Like to see there's yet another person from the Sac area with one of these rigs. There's so many around here!

First things first, you have an AUTO 3.0L that's stock everything, most likely. That means you can't climb hills, period. Neither can a 22RE but at least they admit it and get better gas mileage. Manual transmissions like what I have have a slightly better time since you can control RPMs but not much better. Of course if you mod it like I did, then even going up 80 to Tahoe isn't an issue...

270k miles on the original transmission is quite a lot. Most other manufacturers have the transmissions begin to fail around 200k miles (Toyotas last longer!). I'm not an expert on auto transmissions because I don't have one but to be honest, that transmission isn't going to last much longer. You could try flushing the transmission fluid (helps more than you would think) as well as checking to make sure there's no leaks or anything broken by using the FSM: http://personal.utulsa.edu/~nathan-b...autotrans.html. If you don't know your transmission type, look on the driver's side doorjamb for the code.

A regular tune-up would help performance wise but won't solve the transmission problem.

Lastly, what size tires are you running? Auto transmissions have lower gear ratios than manuals so if you try and put 33"s or something without changing the gear you're going to put a lot of stress on it.

Did you try to manually shift the transmission?

3.0 isn't going uphill in any hurry, especially the automatic.

May be normal operation, might need normal maintenance.

Thanks for the response Gamefreakgc.

I'm not totally sure if it is the original trans or not. The guy I bought it from (it was his wife's DD) but he was a mechanic at Ford and said that he would change the trans fluid about every 6 months, so that should alleviate that issue. But I am keeping a close eye (and feel) for trans slipping or heavy jerks but so far so good.

I am running 31x10.5x15 bfg all terrain's.

Excuse the noob question: but why is it that the Auto 3.0 can't climb hills? (or at least not easily) Is it a power to weight ratio issue?

I didnt start experiencing the issue until after I passed Camino, so going up towards El Dorado Hills area was a bit sluggish but not as severe of issues I encountered the last leg up.

Gsolo-

How do I manually shift the transmission if its AT? I would adjust pedal pressure to the accelerator as that would give me a little control of helping it choose the correct gear.

Almost every sensor, belt, and hose was replaced before I purchased it. Do you recommend me checking anything else out, specifically?

Also it should be noted that when I hit my overdrive option it still says "off" on the dash under the radio. Im not sure if this is just a fuse or what. I am not trying to speed anywhere and like I mentioned I primarily will be driving this in the city (to work and school) so I didnt feel the need to investigate the OD option if that is relevant to my issue? But just wanted to make a note of it.

Your shifter selection should be P R N D 2 L and you have an overdrive off switch.

anything over 40mph (give or take a few) should be in 4th gear, push OD off button and should feel it kick down to 3rd, pull shifter into 2 and it should (maybe harshly) shift into 2nd gear. That would be "manualy" shfiting through the gears verifiying the transmission is operating properly.

Now, the OD OFF light always being off may be a concern...either indicating a possible transmission problem or its just an electrical issue (switch or wiring maybe)

I'm going to be very honest, I'm not that familiar with these older automatics (i'm spoiled working on mostly new stuff) but if my memory is correct there is also a cable from transmission to the throttle...it would have an effect on transmission operation with throttle position. I'll see if I can dig out one of my books....

3.0 (affectionately known as 3.slow) is about 150hp...and a 4runner is usually upwards of 4000lbs, power to weight issue is an understatement. It makes decent torque at very low rpm, then it just kinda makes noise lol

We aren't saying its bad, just not good going uphill at highway speeds. I know with my manual when I still had a 3.0 I had to use 4th gear to stay above 60mph up mountain passes. 4th on a manual is direct drive, same as 3rd gear on your automatic (overdrive off). After 33" tires staying at 70mph up slght hills was hard, 75mph would be just ok...kinda depends on the power band too.

Automatic transmissions have more power loss so you have less power at the wheels. Usually automatic trucks had shorter final gear ratios...4.56 or 4.88 probably in your case. Your 31" tires might be factory tire size, check the sticker in the drivers door pillar.

I was just checking gear ratios the other day for my truck (looking to run 31's since I still have stock tires) and I have 4.56's. A lot of auto transmissions came with 4.10's so that might be part of it. A slower throttle response with larger gears (takes more energy to turn them, much like a mountain bike) but good for cruising speeds.

Yeah that pass is killer for old cars and trucks. Tried it once full with camping gear (probably weighing total about 5000 lbs) before I started modding my engine and couldn't stay above 50 mph. That last hill as you enter El Dorado Hills is especially bad. No stock pickup or 4Runner is going to blaze up those hills.

You're probably right about the 4.10s on non 31" 4runners. Every automatic 31" i've come across has been 4.56 or 4.88.

My manual came with 4.56 and 31" tires

Automatic in overdrive 70mph is about 2100 rpm with 4.10 and 31" and about 2400rpm with 4.56 and 31" tires. Still not as high as a manual in 5th with 4.56 running about 2900 rpm.....so thats another consideration in looking at an automatic running highway speeds, it'll want to downshift to direct drive to keep going.

With stock tires, my truck runs at 3200 RPM at 70 MPH :(. Another reason for me to switch to 31's when these go bald.

From the sounds of it, I might just be stuck with a slug going up steep hills. That's ok with me. As long as it's "normal" for an old heavy beast. I think I might replace the fuel filter just because it's only $30 and Im not sure when it was last replaced. I will try and see about taking a drive up 50 afterwards and see about switching gears manually and see what happens. Now I will have to look into my OD issue. I think I recalled a post asking about AC going up the hill and it was off the whole way.

My issue was the same Gamefreakgc. Packed the 4runner full of camping stuff. Gave me a reason to drink more beer. (less weight on the way home) :)

If you're looking to do a tune-up, here's a list of items to pay attention to:

• Oil change every 3k miles- 5W-30 works great for this area, anything heavier will start to affect MPG's
• Coolant every 30k miles
• Air filter (K&N if you want slightly better throttle response but if you off-road a lot, they tend to not filter dust as well as paper)
• Spark plugs - NGK V-Power work best and are dirt cheap
• Oxygen Sensor - every 80k miles (DENSO are the OEM replacement)
• Cap and Rotor
• Fuel Filter
• Run a couple of Lucas injector cleaners (or Seafoam treatment, if you so desire)
• Check all vacuum hosing for loose connections or breaks. Vacuum leaks can cause power loss.
• TPS adjustment

Here's where I get most of this info from: http://personal.utulsa.edu/~nathan-buchanan/93fsm/

These won't necessarily make your truck run better, but will regain power that was lost to poor maintenance by previous owners. A note on the TPS, just check it per the FSM instructions. If it checks out ok, no worries. If not, adjust. A poorly adjusted TPS on these engines will suck the life right out of it.

These are probably the most sensitive to TPS readings of all of Toyotas I've worked on.

Igntion timing can also cause tempermental issues as well...rule of thumb is to check it when you do a tune up, if you ever get a chance to check with a timing light just set it per factory specs.

Well I drove it yesterday for a short while on highway 50 before it got too steep it was shifting between 3rd and 4th gear. Again not hard jerks. Very smooth and subtle, just doesnt know what gear it feels like being in. Before I was leaning towards fuel filter but now I am thinking that since it is not sure what gear to be in on flat ground and not an issue of not enough fuel getting to the motor to power the beast uphill so I am now thinking maybe the Solenoids are going out. What are your guys' thoughts to this now that it is happening on fairly flat ground?

I think a solenoid issue would cause more problems in the 1 - 2 shift also

The trans only has two solenoids for just the transmission operation.

Possibly could have an issue with the overdrive brake.

How is the fluid level and color?

It might be time for a transmission rebuild.

Looking at the factory manual...if solenoid #2 is malfunctioning you'll only have 1st and 4th gear with the shift in "D"...and only have 1st and third gear with shifter in "2"

Just running through my thoughts there.

now that I think about it, than that makes sense. When I was driving up 50 to tahoe I was either bogged or red lining. Occasionally it would be in the right gear but primarily bogged down. This is what makes me think I might have only had 1st and 4th gear (in that situation) now when I was driving yesterday and it just kept shifting between 3rd and 4th makes me not so sure. I'm really hoping a trans rebuild isnt in my future. I only had plans to keep this truck until I graduated in December so i dont want to keep investing if I dont have to. :s

Try and drive with the overdrive off. It sounds like your driving at a certain speed in between the engines power band making the trans up shift and downshift a lot. Drive with overdrive off and if you still experience the symptoms it's probably something internal.

JasonYota-

the OD light always shows off on the dash. I was driving about 40-50ish yesterday. And in tahoe i would be stuck about 35 mph and bogged or 40 and red lining almost.

What would you think it would be internally?

Also if you guys had to take a guess at a trans build what would you think?

Can you count the shifts when driving? Also don't confuse the torque converter lockup as a gear shift. Have you tried to pull any codes?

I will try to count the shifts next time I drive it. I guess I must have confused the two as I am not sure what the torque converter lockup is.

And I dont have an OBD reader and my check engine light isnt on... yet.