Would it be a dangerous idea to perform the Hoot Flush method with just one person? It seems like you need people to run the truck, drain, refill all at once. I just moved and really have nobody to do this with and I don't want to risk bombing the transmission. Would I be better to just drain the pan, run the truck, drain, repeat? Anyone have any tips?

To expand on this, about how much is safe to pump out at one time? I was thinking of turning the truck on, running .5 gallons out, turning it off, filling it up, and repeating that again twice until I pump out and refill 1.5 gallons.

Thoughts?

Really works great if you get a length of clear plastic tubing to slip over the fitting. Then you can place the bucket or whatever to collect the fluid on the ground beside the driver's door.
I did get my wife to start and stop the engine but don't think it would be a problem for one person to do it all. I tried to measure as close as possible what I took out.
I followed the "hoot" method fairly close and it worked great. I purchased 5 gal. of Transynd and had enough left to change the transfer case and some for future filter changes. I also dropped the pan just to check what was inside and really get all out as possible. Actually an easy job all around.

Check this — one person. http://mdt.volvospeed.com/repairs/allison_atf_filter.html

enahs, thank you for the link, very helpful. Looks as if you can't drain over 2L of fluid at a time, can someone confirm that this is the correct number?

Thank you!

Yep....I did it by myself....worked out well


Good link there enahs:thumb:

Don't worry if you drain out too much before refilling. I did and didn't have enough atf to refill. Tried pulling the truck in the garage and it didnt have enough atf in it to move. It through a couple codes due to the low fluid, but once I filled it up and cleared the codes, everything was fine. That was almost 40k mi ago w/ no problems since.

Really works great if you get a length of clear plastic tubing to slip over the fitting. Then you can place the bucket or whatever to collect the fluid on the ground beside the driver's door.
I did get my wife to start and stop the engine but don't think it would be a problem for one person to do it all. I tried to measure as close as possible what I took out.
I followed the "hoot" method fairly close and it worked great. I purchased 5 gal. of Transynd and had enough left to change the transfer case and some for future filter changes. I also dropped the pan just to check what was inside and really get all out as possible. Actually an easy job all around.

x2, if you get 5/8 re-enforced clear hose you can do it. I used 5ft. to run out to the passenger side, if you got 8ft. I bet you would do just fine. it didn't come out as fast as I thought it would, but only ran the truck for a couple of seconds at a time. :D

I did mine by myself. Stood on passenger side watching clear hose for color to change. Turned off truck as needed from the passenger side. Kept funnel full of fluid in fill tube. Worked great!

I just got done changing mine. Messy job! I must have soaked 20 paper towels. All-in-all it went pretty well though. A note to members with aftermarket exhaust - my MBRP 4" cat delete pipe prevented me from removing the fluid line. I had to loosen the exhaust clamp and wiggle it out about an inch.

I used right at 4 gallons. My local Allison dealership sold my 5 one gallon Transynd jugs and two filters for about $200 including tax.

I didn't notice any better shifting during my warm-up drive. I plan on seeing what it will handle with the Superchip set on performance :)

enahs. Thanks also for the link. It seems like an easy chore. However, can you or anyone else reading this thread tell me that this method is better than just drain and fill the from the plug 4+ times (initially if changing to synthetic). I'm not a transmission expert so I don't know how the mixing occurs when you start the engine. Why did Allison supply this plug?.....I ask this because only 6.5 quarts came out when I pulled the plug but according to the specs, there is 24 quarts in this transmission. If we dropped 6.5 quarts every 15K miles, wouldn't it be easier to utilize just the plug? I don't trust anyone working on my vehicles so I do all maintenance myself (quick lube nightmare 10 years ago.....tranny fluid trail back to my house). Thanks to all that reply.

I just got done changing mine. Messy job! I must have soaked 20 paper towels. All-in-all it went pretty well though. A note to members with aftermarket exhaust - my MBRP 4" cat delete pipe prevented me from removing the fluid line. I had to loosen the exhaust clamp and wiggle it out about an inch.

I used right at 4 gallons. My local Allison dealership sold my 5 one gallon Transynd jugs and two filters for about $200 including tax.

I didn't notice any better shifting during my warm-up drive. I plan on seeing what it will handle with the Superchip set on performance :)


Same thing happened to me with the exhaust being in the way. I used a ratcheting tie down strap around the exhaust and the frame to pull it away a little bit. It gave me just enough room to slide it out.

You can just pull the plug and replace what comes out. But you will always have a blend — even after doing it four times or four hundred times. That's probably OK, but at the price of Transynd, some will want an undiluted result. As was once explained to me, you can line up all the guys on one side of the room and the women on the other and each proceed half way to the middle time after time. In fact, you will never reach one another (in mathematical terms), but you will get close enough "for practical purposes." It is my understanding that Transynd and Dex VI are compatible (but you should check).

I performed the "Hoot method" by myself, it's a piece of cake. I kept track of how much fluid I drained by pouring the old fluid into an an empty gallon jug, that way I knew exactly how much fluid was needed to refill. I ended up using 18 quarts (shallow pan)

Regarding flushing vs draining - Would you consider draining half of your engine oil at the next change? Probably not, so why would you consider draining part of you ATF? At that point what good does switching half of your ATF over to synthetic? Since you will be under the truck anyways, what's another 5 or 10 minutes? Flush it the first time and be done. It is by far the easiest tranny flush I have ever performed.

Next time I may pop the grill out and attach my drain hose at the cooler vs climbing under and disconnecting the return line. A remote start would also be handy when performing this alone.

Can someone confirm that we shouldn't empty out more than 2L at a time as the link says?

CKevo
I'm suprised nobody asked where are you located!!!!?

2 liters is not much, mine went more like a gallon & half a turn. What a mess!

Doug

Located outside of Boston, MA for any nice people :)

mpdlt: Thanks for the feedback, sounds like I will be able to pump a bit out without the transmission grenading on me. Much appreciated.

Hey guys, did the flush today, really wasn't as hard as I thought, I just took it slow, flushed out 1.5L at a time. Had about 2L out of my 5th bottle left at the end for future filter changes. Truck shifts a LOT smoother now. Thanks for everyones help.

I did make a damned mess though when I knocked a jug over trying to shut the truck off. :rolleyes:

What is Transynd and where do you get it?

Is this the recomended fluid to use???

Transynd is a fuill synthetic fluid developed by Castrol and Allison. You can go to Allison's web site to find a dealer near you. You may be able to order it from a supporting vendor. I have an Allison shop near my house.

Transynd IS recommended by Allison but not GM. GM's fluid is a sythetic blend - Dextron IV I believe.

Thanks all for replying. I have an advanced degree in chemistry (don't hold it against me). I have validated the difference in viscosity after 35,000 miles with no major difference. I even go as far as opening my filters to see if there is any difference. Although I'm still a synthetic fan, there is not much difference between synthetic and standard. Where did the raw material come from to make the synthetic? It all comes from crude oil. I buy synthetic because the weight is more consistent.....I'm in a cold weather area. My truck started at -31F last year with synthetic and prefer not to test other oils.
Enahs, I did verify prior to my comment and at 4 changes we still have 31.67% old oil present. I'm just curious why they gave us the plug and hoping someone had a good answer (6.5 quart is not much of a drain). I also heard that the new models do not have the drain plug. Anyone know if this is true?
Just my two cents but if I could do it over again, I would have changed out 6.5 quarts every 10K with standard Dexron III (unless I unfortunately burned the fluid). It held up nice. Thanks.

Has anyone found a place to buy the Castrol labeled version? I would like to make sure they are the same. Thanks.

Transynd is a fuill synthetic fluid developed by Castrol and Allison. You can go to Allison's web site to find a dealer near you. You may be able to order it from a supporting vendor. I have an Allison shop near my house.

Transynd IS recommended by Allison but not GM. GM's fluid is a sythetic blend - Dextron IV I believe.


I am going to assume there is a big price difference?

I just turned 60K on my truck and want to replace the filter - your thoughts - do I need to do a total flush or just the filter?

As I wrote above, five one gallon jugs of the stuff and two filters were had for a little over $200. I chose to empty as much out as possible - hence the Hoot method. Draining the pan netted me almost two gallons IIRC. I did not price the Dextron IV. I bet that stuff ain't cheap either.

I would say if your fluid has not been changed, 60k miles would be a good time to do it. The type of fluid is personal preference.

Since I am running some extra horsepower through the Allison, I thought I would give it every chance to survive... the wife says we will be having issues if I blow this one up to get a Suncoast.

Dont know a whole lot about the Hoot Method.....from my reading it appears you start and stop the engine a few times to get all or as much of the fluid as possible. Could you simply take out the drain plug and then drop the pan? Not recommended to do it that, if so why? I need to look in the manual to see what it says about this and how much fluid it holds.

Thanks again!