Should I change the trans fluid?

[don's 4runner]

I bought a 91 4runner two years ago and it now has 356k on it, I have no idea the last time the trans fluid was changed, so my question is should I change it, or would that open a can of worms and cause more problems. The trans shifts fine and the truck only gets driven about 5k a year.

 

[90toytruck.]

I bought a 91 4runner two years ago and it now has 356k on it, I have no idea the last time the trans fluid was changed, so my question is should I change it, or would that open a can of worms and cause more problems. The trans shifts fine and the truck only gets driven about 5k a year.[/QUOTE



if you have no idea if it has ever been changed you prob want to change the fluid with that kind of milage on it . new filter kit can hurt

 

[salty]

I agree with 90toytruck it is best to start with fresh fluids all around trans,oil evan coolant. If you dont have records when it was last changed then best to start fresh with your own. The only thing I DON'T repeat DON'T recomend is a backflush or system clean that you can purchase at you local "quick lube" shops on hi-mileage vehicles this can actualy do more harm than good. Have fun with your ride...

 

[4mydogs]

The only thing I DON'T repeat DON'T recomend is a backflush or system clean that you can purchase at you local "quick lube" shops on hi-mileage vehicles this can actualy do more harm than good.

I agree wholeheartedly. My transmission never gave me a lick of trouble, until a shop did that to it. On my next road trip (Interstate) the Trans Temp light came on, and I pulled over to find the back of the truck covered in transmission fluid. From then on, that #@)%^ light would come on sometime during every road trip. No one could tell me why. The fluid never has taken on that burnt smell, which I think it would have if it was actually overheating. I eventually installed a transmission temp gauge so I could keep an eye on it. Guess what? The light never came on again.

Personally, I've taken several vehicles beyond the 200,000 mile mark, and never messed with the transmission fluid on any of them until this truck, and never had any transmission trouble or idiot lights until this truck. I wouldn't change it out, just check it for any signs of overheating (burnt smell). But don't take my advice -- I'm just a grumpy old faht.

 

[salty]

I agree wholeheartedly. My transmission never gave me a lick of trouble, until a shop did that to it. On my next road trip (Interstate) the Trans Temp light came on, and I pulled over to find the back of the truck covered in transmission fluid. From then on, that #@)%^ light would come on sometime during every road trip. No one could tell me why.

What happens alot of times the backflush loosens a vital component that is built up on alot of the parts inside the trans. It is the "varnish" that has built up over time. Belive it or not this "vanish" is like a protective coat on many moving parts. If you "wash" this off not only are you "cleaning" your parts but you are stripping off this protective coat. Some of this loosen "vanish" plugs breather vents, Vanes in the valvebody, and may even (this is funny but true) "unglue?" parts that were working together when the vanish was there. Any ways I'm blabbing on now. sorry. I have not talked to anyone that has had the trans backflush done and they leave happy. My self included.

 

[4mydogs]

What happens alot of times the backflush loosens a vital component that is built up on alot of the parts inside the trans. It is the "varnish" that has built up over time. Belive it or not this "vanish" is like a protective coat on many moving parts. If you "wash" this off not only are you "cleaning" your parts but you are stripping off this protective coat. Some of this loosen "vanish" plugs breather vents, Vanes in the valvebody, and may even (this is funny but true) "unglue?" parts that were working together when the vanish was there. Any ways I'm blabbing on now. sorry. I have not talked to anyone that has had the trans backflush done and they leave happy. My self included.

That's interesting, and makes sense. It seems like many is the 4Runner owner who has experienced this.

 

[wjamyers]

is everyone talking about AT or MT?

 

[salty]

is everyone talking about AT or MT?

I am refering to AT. I dont know of any "Backflush" service for a MT.

 

[wjamyers]

thanks

 

[Dumpsterdiver]

I just bought a 95 280,000 km's and the ATF was VERY dark. No burnt smell just very dark, I question if it was ever changed. I found these instructions to be very helpful: http://www.toyota-4runner.org/maint...on-service-4th-gen-t4rs-prior.html#post393776 I had to drop the cross member to get the pan off to get at the filter and it took me the better part of half the day to finish the job with a complete flush (20 liters total) but I would recommend you do it. It shifts a little smoother and I have the peace of mind that it's nice and clean. I too wouldn't recommend a back flush, more harm that good. The cost of oil and filter was less than $100.