Sluggish at low speed after transmission leak repair

[karyins]

2004 4wd v6 had a transmission leak recently. http://www.toyota-4runner.org/4th-gen-t4rs/225232-can-i-drive-5-miles-leaking-transmission.html Engine would rev to 2000 before it move from a full stop. Went to garage and had the leaking transmission cooler line replaced. The garage didn't add enough transmission fluid at first so I went back and they poured another bottle in.

The 4runner drove smoothly for about 100 miles then I noticed that it started to feel sluggish again at low speed. Normally the gas pedal is really sensitive, I only need to touch it slightly to make it to go from a full stop and I barely hear the engine rev up. For the lack of a better description, it kinda feels like a "bunny" jumping out from a full stop. Now I need to step down the gas pedal and the truck would move out slowly till the engine rev up to 1500 and then the truck would really go. It doesn't stall like before the leak repair but it's really sluggish, feels like it's struggling. I also feel like the engine rev up more at 20 30 MPH on local roads. It seems like it needs more gas to do the same work now.

I checked the transmission fluid level again and found out that the garage added a little too more this time (about 1/2 inch higher than the upper notch of the "hot" mark on the dipstick, when the engine was running hot), so I siphoned about 6oz out to make it at proper level. Then I drove a couple miles but the symptom is still here. I will try it again tomorrow.

Any idea what might have caused this?

Thanks!

P.S. The truck does have both CV boots leaking for at least 4000 miles now. It used to make clunk sound in U-turn but somehow not anymore. And I drive in 4wd only a bit every month to keep it alive. Not sure if it's related but maybe it's time to finally get those repaired too.

 

[TechWrench]

2004 4wd v6 had a transmission leak recently. http://www.toyota-4runner.org/4th-gen-t4rs/225232-can-i-drive-5-miles-leaking-transmission.html Engine would rev to 2000 before it move from a full stop. Went to garage and had the leaking transmission cooler line replaced. The garage didn't add enough transmission fluid at first so I went back and they poured another bottle in.

The 4runner drove smoothly for about 100 miles then I noticed that it started to feel sluggish again at low speed. Normally the gas pedal is really sensitive, I only need to touch it slightly to make it to go from a full stop and I barely hear the engine rev up. For the lack of a better description, it kinda feels like a "bunny" jumping out from a full stop. Now I need to step down the gas pedal and the truck would move out slowly till the engine rev up to 1500 and then the truck would really go. It doesn't stall like before the leak repair but it's really sluggish, feels like it's struggling. I also feel like the engine rev up more at 20 30 MPH on local roads. It seems like it needs more gas to do the same work now.

I checked the transmission fluid level again and found out that the garage added a little too more this time (about 1/2 inch higher than the upper notch of the "hot" mark on the dipstick, when the engine was running hot), so I siphoned about 6oz out to make it at proper level. Then I drove a couple miles but the symptom is still here. I will try it again tomorrow.

Any idea what might have caused this?

Thanks!

P.S. The truck does have both CV boots leaking for at least 4000 miles now. It used to make clunk sound in U-turn but somehow not anymore. And I drive in 4wd only a bit every month to keep it alive. Not sure if it's related but maybe it's time to finally get those repaired too.

I sounds like the previous low fluid issues did some damage to the trans clutch packs. If so, the only fix is an overhaul or replacement trans. One last ditch hope would be to remove the lower trans pan, and replace the internal filter, just in case it has become clogged with material, and not passing fluid to the pump quick enough. This, would be a long shot, because if the filter is clogged, the only material that would cause this is from inside the trans clutch packs. Which means clutch wear has already started because of the low fluid condition. And even when the fluid level is returned to normal, the material that has worn off the clutches can't be replaced without replacing the clutch disks, which involves an overhaul. Also, the issues with the leaking CV boots should have no impact on how the trans works.

Wish you luck.

 

[karyins]

I sounds like the previous low fluid issues did some damage to the trans clutch packs. If so, the only fix is an overhaul or replacement trans. One last ditch hope would be to remove the lower trans pan, and replace the internal filter, just in case it has become clogged with material, and not passing fluid to the pump quick enough. This, would be a long shot, because if the filter is clogged, the only material that would cause this is from inside the trans clutch packs. Which means clutch wear has already started because of the low fluid condition. And even when the fluid level is returned to normal, the material that has worn off the clutches can't be replaced without replacing the clutch disks, which involves an overhaul. Also, the issues with the leaking CV boots should have no impact on how the trans works.

Wish you luck.

Thanks for the input! I'll take it to the garage again. I was hoping it's because of too much trans fluid (google says it causes foaming and shifting problems), or maybe they used the wrong type of fluid.

It did run smoothly for about 100 miles though after the leak repair. Hope I won't need an expensive trans replacement!

 

[BlackWorksInc]

It's possible the transmission is unfortunately toast.

You could try to clean the Throttle Body itself (do this with the key off), then disconnect the battery for 10minutes or so. Reconnect it, let it idle with no loads for 5~10mins (no A/C, headlights, ect), then drive it normally for about 10miles.

That should help the vehicle relearn the idle and relearn the shift mapping (the small range of leeway the ECM is allowed to adjust engine RPM and shifting to smooth out the feeling of shifting between gears)

If that doesn't really work, then it's possible the transmission is damaged.

 

[karyins]

It's possible the transmission is unfortunately toast.

You could try to clean the Throttle Body itself (do this with the key off), then disconnect the battery for 10minutes or so. Reconnect it, let it idle with no loads for 5~10mins (no A/C, headlights, ect), then drive it normally for about 10miles.

That should help the vehicle relearn the idle and relearn the shift mapping (the small range of leeway the ECM is allowed to adjust engine RPM and shifting to smooth out the feeling of shifting between gears)

If that doesn't really work, then it's possible the transmission is damaged.

I'm no expert and maybe I just don't want hear the bad news :redbrick:. But if the transmission was mechanically damaged before the leak repair, shouldn't I feel it immediately when I left the garage? It ran smoothly for about 100 miles then the sluggish feeling returned. It's not crawling either, just not as responsive at taking off and seems the engine needs to work harder. If I never drove it before I probably would think it's normal.

Anyway wish me luck!

 

[brownh]

I'm no expert and maybe I just don't want hear the bad news :redbrick:. But if the transmission was mechanically damaged before the leak repair, shouldn't I feel it immediately when I left the garage? It ran smoothly for about 100 miles then the sluggish feeling returned. It's not crawling either, just not as responsive at taking off and seems the engine needs to work harder. If I never drove it before I probably would think it's normal.

Anyway wish me luck!

Check to make sure your dropping into first gead sounds like you possibly starting off in 2nd if thats the case you could have a sticky 1/2 shift solenoid , if thats the case remove the pan and make sure the sub harnes or solenoid isnt melted due to excessive heat from driving it ow on fluid

Regards,
Toyota MDT

 

[brownh]

I meant to say gear instead of geed alsoI meant from driving it low on fluid also see if when you back up the trans doesn't clunk its programmed to go from reverse to 3rd then to first when shifting from reverse to drive . Also check to see what your cts is reading the trans programing will cause a late shift in order to fast heat the cats in order to reduce emissions if the pcm gets a false input . Last but the most important is to verify that you have the corrected fluid genuine Toyota .remember after anything is done to disconnect the battery to reset the fuzzy logic learned by the pcm.

 

[BlackWorksInc]

I'm no expert and maybe I just don't want hear the bad news :redbrick:. But if the transmission was mechanically damaged before the leak repair, shouldn't I feel it immediately when I left the garage? It ran smoothly for about 100 miles then the sluggish feeling returned. It's not crawling either, just not as responsive at taking off and seems the engine needs to work harder. If I never drove it before I probably would think it's normal.

Anyway wish me luck!

It's a possibility at this point, I would note that it COULD be the issue; but let's try to rule other things out since it did run well for a bit.

 

[brownh]

I also wanted to make sure there's nothing rattling around with the engine transmission or drive line. This includes tire balance . I have seen the piezo electric crystal knock sensors pic up on a NVH issue ang the PCM is designed to pull all timing back in an effort to save the engine instead of detonation

 

[karyins]

I also wanted to make sure there's nothing rattling around with the engine transmission or drive line. This includes tire balance . I have seen the piezo electric crystal knock sensors pic up on a NVH issue ang the PCM is designed to pull all timing back in an effort to save the engine instead of detonation

Lots info to process. Thanks!

I don't know what transmission fluid they used the first time. But the 2nd time they didn't use Toyota stuff. I saw the bottle, it's another brand. Now I hope it's compatible. Would different trans fluid cause the sluggish problem in such a short time? I siphoned about 6 oz trans fluid out and it's dark red, kinda sticky but seems no particles in it.

There's no clunk sound anywhere. I did hear a grinding sound in U-turns when I was testing drive it yesterday. But the sound went away when I did some full left and right circles in an empty parking lot. I assume that sound came from the CV joints with bad CV boots.

I can reverse fine. I think the tires are balanced. I hooked up a code scanner and there's no fault code.

Another thing, maybe I am just being paranoid, but when I open the engine cover, I noticed there's this wire (tube?) kinda curve up on the side. I mean, I have never noticed it before, almost like someone pulled it up from somewhere down there. What's this wire? Could it cause the problem? LOL, anyone?

Thanks a bunch!

 

[karyins]

It's a possibility at this point, I would note that it COULD be the issue; but let's try to rule other things out since it did run well for a bit.

Yeap that's why I came here

 

[karyins]

I went to the garage again. The guy took me on a test drive for about 10 minutes and told me everything is OK. Gear shifts fine, no weird sound coming from transmission, power kicks in at the right moment etc. He also confirmed that they used compatible transmission oil. He mentioned the correct type of oil on the spot so I believe him. Anyway he is really nice and totally not trying to sell me anything so I trust him.

OK I think I might have been just a little paranoid!

Thank you all awesome guys here! Best go to place for a car noob like me!