GOt the tranny flushed yesterday and had Amsoil synthetic put in.... today I notice it likes to down shift a lot... at around 75mph it usually does around 2400 RPM, jumps up to 2900 quite a bit. A bit later it jumps to 3500 while in cruise, and stays there. Won't come back down even going downhill! Happened 3 times in a familiar place, very slight hills at that (South Dakota). Any ideas what the heck is going on? When I got off the interstate and parked it I heard the tick tick tick sound of something hot cooling down, like exhaust systems sometimes do but it appeared more from the tranny area (sound has never been noticed before). Please help!! Oh, this is on a 98 automatic 3.4 if you hadn't figured that out yet.

 

How was it flushed? Have you checked the fluid condition and level?

 

how many miles are on your truck and when was the fluid changed last? sometimes a flush can do more harm then good when the fluid is bad.

 

I've got 118,000 on it, not sure when it was last changed.... which is basically why I changed it, so I KNEW where it was at. Have had no issues with it previously. It was a full flush, which included "adding transmission cleaner, flushing of transmission cooler, cooler lines, valve body, and torque converter. Flush all contaminated fluid out and replace with fresh fluid, add conditioner and test fluid level." They used 15 quarts of Amsoil. From what I know, this is the most complete procedure, which is why I went where I did.

 

yeah I have been battling this question as well because i just bought a 98 with 76k on it na dthe fluid wasnt chnaged since 35k. when i drained it the fluid was pretty brown. I have heard from a few people that if your fluid is burnt you shouldnt flush because you can dislodge particles that may be holding some things together and the flush could cause more problems. Hopefully this is not the case. Did you see how the used fluid looked? If you do a search on here you can here some horror stories about older trannies being flushed. My local toyota stealership wont flush trannies though many do. Also look at gadget's site, he says not to flush if your fluid is bad.

 

What conditioner did they add ? I added Lubegard red to to mobil 1 syn, it solved hard shifting problem.

 

Ive been draing and refillign with mobil 1 syn. Havent noticed any hard shifts? should I add this lubegard? whats its purpose and where can you find it?

 

2001 4Runner SR5 V6 4WD. 86,000 miles. I check my dipstick every once in a while. The fluid smells like new and is still red.

I personally think that some people go overboard with the "maintenance" of their automatic transmissions.

I change my engine oil every 3K, rotate my tires, replace plugs and the air filter. I keep my driveline zerks lubed and have changed the fluid in my diffs and transfer case. The truck runs exactly like it did when I purchased it almost 4 years ago.

If you tow with your 4Runner, I can see the logic in changing the fluid every 50,000 or so miles.

Andreas

 

Hmmm, I was just considering having my trans fluid flushed with Amsoil and you had to go and post this! :-P

I have a '03 Taco DoubleCab with 45k miles. I installed a tranny cooler when I bought it, and have did the drain and fill of the tranny once. I tow a 4000 lb boat pretty regularly in the summer time.

Amsoil recently added Toyota T-IV fluid to thier compatibility list for thier universal ATF, that is why I was considering switching.

Anyone else with any experience with the Amsoil ATF in a tranny that requires Toyota T-IV fluid??

 

i dont think his problem is with the amsoil. I think its with the flush. It could have knocked loose debris that was actually helping the tranny. Sound weird but it seems to be true. You should be fine since youre truck has low mileage and you have changed the fluid before.

 

I would drop the pan and change the filter (screen). It is possible that you have a restriction in the filter.

 

Okay, here's another thought.... I'm pretty mechanically inclined, but not at these transmissions. They are electronically controlled, correct? It's like it no longer knows how to downshift correctly, or simply doesn't upshift by itself.... are there any sensors or any sort of beast that could have been affected by this procedure? I totally disagree with the idea that you should think that loose debris inside the tranny actually helps. That's BS. Metal filings get picked up by the magnet, and "junk" gets caught by the filter. That's what those two devices are for. From the sounds of it, Toyota has some pretty solid trannys. Not too often you hear of them "going" like on our domestic counterparts. I'm gonna have to do a bit more investigating on this one. I just scratch my head when I did something that by all accounts should HELP and then this comes about.... I do have the worse luck ever too, hopefully that's not coming into play on this...

 

I have to agree with you on this whole idea the 'loose' stuff in the transmission is somehow holding it together and a flush will cause it to fall apart. There is some truth to the idea that a flush can instigate a problem in what one thinks is a good running unit, but not for the reasons mentioned above. I was in the transmission business for a long time, and what most often happens is this. The transmission fluid starts to fail because of a heat problem, and the fluid starts to turn brown and smell burnt. As it fails, it starts to leave varnish deposits in the interior surfaces of the unit. And, if left too long, the clutch packs start to slip because of failing/hardening seals. The slippage causes material to wear from the friction disks and travel with the fluid until it gets caught in the filter or lies in the bottom of the pan. Now someone finally checks the fluid and notices the color or smell and decides a fluid change will fix it all up. The new fluid, with all its fresh additives will often cause the varnish deposits to break down and stirr up the material deposits. Some of this stuff is fine enough to pass thru the filter/screen, and can then get stuck in a valve or solenoid and cause it to malfunction. Next thing you know, they are blaming the new fluid for ruining what they thought was a 'good' transmission. The transmission was already on its way out, the new fluid just hastened it a little.

The other problem that can be caused by a flush is using the wrong type of fluid. Many of the newer units are very sensitive to fluid type. Different types of fluid have special mixtures of additives that are designed for certain applications. If your transmission was designed to work with a certain type of fluid, and you add fluid with a different additive recipe, it may not work as designed.

If a transmission is in good mechanical condition, the proper fluid is used, and the flush is done properly, it shouldn't cause any problem. If after a flush, the transmission acts up, one of the above was wrong.

 

Thank you! Couldn't really ask for much better an explanation.... I don't necessarily think I'm looking at failure here, or at least I hope not. I'm gonna have to do some more investigating/waiting either way... Thanks though!

 

i had a 75 ihc scout with 100,000 miles on it, did the flush and filter thing, thought i was doing right, the thing never went in reverse again, it was still like that when i gave it away if the tranny hasnt been serviced regularly, or if you are not sure my advice would be to leave it alone, but i guess it's too late for that, huh? start saving for a rebuild friend

 

could be temp sensor

 

this is a great discussion. 2000 4runner with the 3.4 and I just had my transmission flushed by a reputable shop at around 80k. fluid dark enough to not transmit sunlight when in a 1L pepsi plastic bottle. however, I didn't replace with syn but when with dex, plan on doing syn after another 30-50k when I install a tranny cooler. my only 2c is the dude that did the work told me that on the toyota trannies filters are set using long bolts with the nuts hidden up in the tranny. anyone know if this is true. this was his reasoning for not removing the filter but simply cleaning it in place. no problems with hard shifting, only noticed that now when the fluid is cold it takes a little bit for it to downshift until it gets warm, which I attribute to the new fluid doing it's job, keeping the tranny cool and it is probably a little thicker when new.

 

I've been going through a similar experience, however mine was triggered by a CEL P0770 and PO773 re: soleniod E. About 4k(all highway miles) after a tranny flush, cleaning kit, and refill... the light came on. It kept coming on periodically after I would pull the code. I put in some BG tranny stuff. Light has come on a few times since then, but usually stays off even in mountain driving. Prior to my flush, I had burnt fluid and probably a bunch of tiny particals from the flush that still make it through the screen into the solenoid hole. It seems that the BG has broken down those tiny particles and maybe now I should drop the pan, clean the screen, and replace the fluid again sooner than later. My new (and highly recommended) mechanic thinks that might be overkill if the BG has done it's job. So far the CEL's appearance has become more and more rare. I'm in standby mode right now.

 

Sorry, '95 T100 A/T 5VZE 131,00mi. Mentioned service was at 122,000 miles.

 

I love my 5-speed.