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Unread 02-23-2008, 06:22 AM   #16
RJV
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Quote:
Originally Posted by Windowsrookie View Post
Do what you want, but I would never flush a transmission. If you want to get all of the fluid out disconnect one of the hoses and let the transmission pump the fluid out itself.
WOW! I would never do that. Pulling a hose off a cooler hose on a trans would be like pulling a cooler hose off of you engine oil cooler. Would you want to run your engine without oil?

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Unread 02-23-2008, 06:29 AM   #17
JBN311
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Quote:
Originally Posted by greasefingers View Post
If you are worried about replacing most of the fluid, then replace the fluid twice over two weekends.
I was just milling over this and your Idea seems good. None of the quick change places that are open on weekends will change the filters. I was losing sleep on how I could get new fluid/filters in without putting cheaper fluid in after I change the filter, THEN going to get a flush and put the good stuff in.

Thanks alot.
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Unread 02-23-2008, 06:29 AM   #18
greasefingers
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Quote:
Originally Posted by RJV View Post
WOW! I would never do that. Pulling a hose off a cooler hose on a trans would be like pulling a cooler hose off of you engine oil cooler. Would you want to run your engine without oil?
I have done this twice on two vehicles. You fill the tranz up at the same rate that it is being pumped out. But it can be messy and it is not for novice DIY-erís.
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Unread 02-23-2008, 07:59 AM   #19
RJV
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Quote:
Originally Posted by greasefingers View Post
I have done this twice on two vehicles. You fill the tranz up at the same rate that it is being pumped out. But it can be messy and it is not for novice DIY-erís.
So what is the difference between that and a flush?
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Unread 02-23-2008, 08:08 AM   #20
Windowsrookie
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Quote:
Originally Posted by RJV View Post
WOW! I would never do that. Pulling a hose off a cooler hose on a trans would be like pulling a cooler hose off of you engine oil cooler. Would you want to run your engine without oil?
No, it's not the same actually. Run the transmission in neutral so it pumps out the fluid. Transmission isn't going to overheat, you're not moving. have a friend pour fluid in the top and stop when you see the color change.
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Unread 02-23-2008, 08:34 AM   #21
RJV
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Quote:
Originally Posted by Windowsrookie View Post
No, it's not the same actually. Run the transmission in neutral so it pumps out the fluid. Transmission isn't going to overheat, you're not moving. have a friend pour fluid in the top and stop when you see the color change.
The way I read his post was he was pulling off a cooler hose and draining the transmission, then adding fluid. My bad.
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Unread 02-23-2008, 03:14 PM   #22
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Originally Posted by greasefingers View Post
I have done this twice on two vehicles. You fill the tranz up at the same rate that it is being pumped out. But it can be messy and it is not for novice DIY-erís.
Steve's got that right...MESSY!

I always recommend adding a drain plug when changing the filter(s). It's inexpensive and then you can drain the fluid once again without dropping the pan if you feel uncomfortable with just the filter change and 6 qts. of new fluid. Even after a couple of additional drains, you'll never get the "old" fluid completely removed, but the percentage of new fluid increases with each refill.

IMHO it's totally unnecessary labor to do the additional drains, but if it makes one feel better, go for it.
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Unread 02-23-2008, 03:43 PM   #23
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Quote:
Originally Posted by greasefingers View Post
To flush a perfectly fine operating tranz is only asking for trouble. Remove the pan and replace the filter and then fill thru the tranz dip stick. If you are worried about replacing most of the fluid, then replace the fluid twice over two weekends.

What is everybody's issue w/ flushing a trans that only has 60k on it?
I would agree if it was over 100k...but not on 1 with only 60k.
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Unread 02-23-2008, 03:51 PM   #24
chrisstromberg
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drain plug

turbonut- What kind of drain plug do you use for your transmission? I have a fumato valve on my oil pan but I haven't heard of using one on the transmission.
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Unread 02-23-2008, 06:05 PM   #25
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Originally Posted by chrisstromberg View Post
turbonut- What kind of drain plug do you use for your transmission? I have a fumato valve on my oil pan but I haven't heard of using one on the transmission.
Never used the Fumoto valve as I was always afraid that it may be hit accidently when on the road.
I believe this is the one I installed, but a generic brand can be purchased at most parts stores:

http://store.summitracing.com/partdetail.asp?autofilter=1&part=BMM%2D80250&N=700 +%2D120229+115&autoview=sku
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Unread 02-23-2008, 08:21 PM   #26
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Even though the tranz fluid is about an order of magnitude cleaner than the motor oil, it is still necessary to change it often (every 30,000 miles on older Jeeps). Some newer vehicles out there have 100,000 mile ATF. Some special coolants can also go this far, but both are much more expensive.

The difference between motor oil and AFT is that the motor is contaminated from blow-by gases (gases that escape past the piston rings Ö even on brand new engines) Thatís what makes the oil black (carbon and exhaust gases) The AFT does not see this but it does get metal particles from wear & tear and the additives break down over time. The filter will protect from the metal particles but only a fluid replacement can replace the additives.

Flushing an electronic/mechanical operated transmission is never a great idea. There are too many sensors and solenoids.

I actually have never seen a dirty tranz filter on a Jeep, but I guess it is the finer particles that can not be seen, that can restrict flow?

The tranny hold about 12 quarts! Only 5 can be drained however.

A drain plug/valve in the tranny pan WOULD have been a great OEM design.
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Unread 02-23-2008, 09:46 PM   #27
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Well, I changed the filters today, intead of getting an entire flush. I decided against the flush because the ATF was very red and not milky. It was actually pretty straight forward....messy.....but straight forward none the less.

Thanks for the input guys!
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Unread 02-23-2008, 11:21 PM   #28
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Quote:
Originally Posted by greasefingers View Post
Even though the tranz fluid is about an order of magnitude cleaner than the motor oil, it is still necessary to change it often (every 30,000 miles on older Jeeps). Some newer vehicles out there have 100,000 mile ATF. Some special coolants can also go this far, but both are much more expensive.

The difference between motor oil and AFT is that the motor is contaminated from blow-by gases (gases that escape past the piston rings Ö even on brand new engines) Thatís what makes the oil black (carbon and exhaust gases) The AFT does not see this but it does get metal particles from wear & tear and the additives break down over time. The filter will protect from the metal particles but only a fluid replacement can replace the additives.

Flushing an electronic/mechanical operated transmission is never a great idea. There are too many sensors and solenoids.

I actually have never seen a dirty tranz filter on a Jeep, but I guess it is the finer particles that can not be seen, that can restrict flow?

The tranny hold about 12 quarts! Only 5 can be drained however.

A drain plug/valve in the tranny pan WOULD have been a great OEM design.
A tranny flush machine hooks up in the tranny cooler line and uses the trans pump to evacuate the fluid while the machines pump introduces new fluid into the transmission "completing the circuit"

I think you have bad information or a different spin on what a transmission flush means either way you couldn't be farther away from being accurate
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Unread 02-24-2008, 04:42 AM   #29
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Quote:
Originally Posted by Envygreen View Post
A tranny flush machine hooks up in the tranny cooler line and uses the trans pump to evacuate the fluid while the machines pump introduces new fluid into the transmission "completing the circuit"

I think you have bad information or a different spin on what a transmission flush means either way you couldn't be farther away from being accurate
I don't knpw about that. It all depends on what type of machine you're using.
The type you describe is OK, (except for the fact that the pan probably won't get dropped and the filter changed).
Then there is the machine that gets hooked up to the tranny pump suction (after filter removal), the tranny is run, and the old fluid gets collected and discarded as it comes out. This is probably the best.
Then you have this type which I believe could cause big trouble:
http://www.asedeals.com/transmission_flusher.html
"EXCLUSIVE "POWER-FLUSH" AIR AGITATION FEATURE
The Ranger RT-15X is the only machine in the world to combine the powerful cleaning action of pressurized air to remove impurities from transmission components, filter and cooler lines. Although not required for typical services, additional profits can be made by offering full service cleaning instead of just fluid replacement."
[my bold]
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Unread 02-24-2008, 05:20 AM   #30
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Quote:
Originally Posted by Envygreen View Post
I think you have bad information or a different spin on what a transmission flush means either way you couldn't be farther away from being accurate
Yes I know about the machines for flushing. Two things that I do not like: 1- as SJZ mentioned the filter does not get replaced. 2- the machine has AFT left over in it from the last job which needs to be chased out. I do not trust them to waste a quart or two of AFT+4 to clean it. They need more than one case of AFT+4 to do the job properly.

Also if you rely on the DYI method, then the flush is gentle. The flow rate of the flush is the same as the transmission is the pump. I do not know if a machine built for flushing can closely match this flow rate? If not then gung may get stirred up.
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