effects4

never flush a transmission?? lol thats like saying never change your oil, just change the filter and top off. SMH

wolfy53

I know I'm not the norm, but I flush my transmission! My thoughts you need to change the fluids period. I have never had any issues. Now my guy does the flush and then I have them drop the pan and change the filter. My truck has 120k miles on it. Shift perfect. I had it flushed at 100k miles. So I know nothing of what was done before.

The machine they use uses the transmission pump to "flush" the fluid through it. Its not forcing anything in. Why not replace all your fluid? You could also just drain 1/10 of your oil and then top off...

techrep

iTrader: (1)

when people jump on here and say stupid crap...makes me lol

primalurges

well reality is the jury is still out on this one as you can see by the varying opinions. I owned an 88 jeep that I never changed the tranny oil on and it went 160k before I sold it. Tranny was perfect. My 04 F150 went for 120k before it dropped the tranny and that went to dealer for tranny service every 30k.

screamineagle

Hey if you feel safe flushing, by all means flush away! Not my tranny though. I have never seen anything good come from flushing a transmission.

And to compare flushing to changing your engine oil? That's just an uneducated statement.

wolfy53

Doug I respectfully disagree. I have had nothing but great luck doing a flush, but I always drop the pan and change the filter afterward. Have our original family owned toyota t-100. The transmission has been flushed 4 times now in the last 15 years and 140k miles. Never a problem.

On my "new" f-150 I bought a year and a half ago, it had 98k miles on it. I had the trans flushed, and the filter changed. I have 118k miles on it now and no problems. But I have no clue on what was done before. It could have been original fluid for all I know

For me I want all that old fluid out. That's just me. Why wouldn't you want new fluid in there instead of 10-20% new? Not sounding rude just curious to why some people are so against it?

djfllmn

iTrader: (1)

because a flush machine can dislodge debris and it gets places it shouldnt be...and you get a lot more than 20% out by dropping the pan...its safer to drop the pan than flush it

dukedave5200

Flushing can be done a couple different ways and shops have a couple different machines that work a little differently. What you generally want to avoid are the machines that use their own pressure to push in the new fluids - this is where things can go wrong. The other kind of machine basically uses the transmissions own pressure while the engine is running to cycle the fluids - this is also the method you can do on your own (using the radiator lines and a couple of buckets.)

Never flush using the first method or high pressure machine.

The older the transmission is, and the longer it's been without a service, the riskier it is it to do anything to it. Flushing and even just replacing fluid all at once in an old transmission can mess it up. But, a 10 year old transmission no matter how many miles is really not going to have anything bad happen flush or drop.

Mattloz

I was thinking dropping the pan and put cheap mercon v ( like valvolin ) run a little to get the oil in the converter out then drop it again and do it one more time and then but good mercon v (like mobile1) and call it a day I'm not ready nor have the money ( or my parents) to get it flush and if worse case senerio my tranny taking a **** so I'll take the safe way and slow flush the tranny because I need my truck I rather spend $200 dollars on oil and slow flush it rather spend 2000 on a blown tranny but thanks for the input guys I really appreciate it

screamineagle

I respect your disagreeing but how does a pan drop yield only a 10-20% transfer of fluid? I mean really, that's an absurd (to say the least) lack of factual reality. But anyway.... The reason I refuse to flush my transmission is because I don't want crud blocking my valve body passages. BTW, I'm at 193,000 miles on my original never flushed transmission.