2001 to 2010 Allison Transmission Flush

In this video, you will learn the easiest and quickest way to flush an Allison Transmission without removing the airbox. I will tell you the do's and don'ts and how to flush your transmission. You will also learn the torque specs and when to change your transmission fluid.
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[@FreeSpeechIsFreedom]

This is the best most helpful video on changing the Allison 1000 Transmission Fluid I’ve seen out of about 20 I’ve watched. Excellent work and thank you for providing this for us to view 👍👍👍👍

[@fixitjohn]

Hey Rico, Thank you for the nice comment. I am glad it helped if you have any questions just ask.I will try to help. Thanks for watching.

[@FreeSpeechIsFreedom]

@@fixitjohn Awesome John! thank you very much!

[@CaptK-py8rq]

Really good video John, thank you for sharing your knowledge. We have a 2004, 3500 Silverado crew dually with the Allison 1000 I believe, coming up on 70,000, we mainly just use it to pull the horses. I believe when it warms up a bit, I'll flush ours as you described. Always wondered how to do all fluid, not just the pan and two filters. Thank you again, I did subscribe as well.

[@fixitjohn]

Thank you Capt. Kevin, It is comments like this one that keeps me motivated to help others. Thanks for subscribing to my channel.

[@joewallis9]

He tells it like it is very helpfull

[@fixitjohn]

Thanks a bunch.

[@underdog576967]

Just curious why doing 8 quarts instead of four flushing ? To be more thorough? Best video I’ve seen , Thankyou

[@fixitjohn]

I wanted to get all the old out. I hope this answers your question. Thanks for watching.

[@Jc-bo1uu]

I use Amsoil and it is really the best you can get if you ask me. And I got mine done at the dealership at 46,000 mils and with amsoil you can run it up to 100,000 mils. And I have a 2019 with the L5P and the owners manual says to change the transmission fluid at 90,000 miles normal service. Severe service change automatic transmission fluid at 45,000 mils. So the 1st time I did mine was at 45,000 mils. And the 2ed time I will do it again at 100,000 to 120,000 mils and go from there. The 1st time win I took it to the dealership and provided them the transmission fluid to do the flush they only changed the external spin on filter. They sed the pan filter will come out clean so it would be a waste of money to change the internal filter. So I decided to do that the 2ed time around, change the internal filter. And the pan gasket is a reusable pan gasket.

[@Jc-bo1uu]

And to do a full transmission flush you should have used 20 quarts.

[@fixitjohn]

Thanks for watching

[@CMac0517]

Great video. So I am clear, You add 7.4 to the pan then you cycle gears while extracting 2 QTS then you add 2 then extract 2 then add 2. Repeat that until you have 8 total QTS extracted . Then after all 8 QTS are extracted you add the remaining 5 to equal a total of 12.4 QTS to the entire system ? Also is it inch pounds or Ft pounds for the bolts on the pan. Thank You John!

[@fixitjohn]

Or thereabout.

[@nadianicolae6485]

Can you explain wich hose exactly that you disconnected i can t be sure . thank you

[@fixitjohn]

Sure the hose that I disconnected was the return line back to the transmission. It is simple. Keep the money in your pocket and you will know that it was done right. Thank you for watching.

[@20083500HD]

I never had an issue with draining all the old fluid out and replacing what I drained

[@fixitjohn]

I am glad for you.

[@ishdhillon4145]

Isn’t the sump filter only changed during overhaul ?

[@fixitjohn]

Not on my vehicles. That is a pricey tranny I am not taking any chances. Thanks for watching. Let me know what you think.

[@user-wj9wq7mk4h]

I noticed you were talking about there not being any band adjustments. Allison's don't use bands....

[@fixitjohn]

Yes you are correct. Thanks for watching.

[@DannyC379]

So I tried to flush my trans using your method today. Fluid started pouring out of the trans where this line goes. Why would that be?

[@fixitjohn]

Yes, a little will come out of it. I would not be concerned about it. If it is gushing out you may have it hooked up to the wrong tranny line. Good luck and thank you for watching.

[@DannyC379]

@@fixitjohn it was gushing pretty good. I made sure to hook it to the top line. The one that says “From Cooler”. I think I may have other issues. The transmission shifts fine. Drives normal. But within 20 miles the temp will be over 200.

[@fixitjohn]

@@DannyC379 those Allison run hot anyway. Good luck.

[@minombremiapedillo534]

Did you reuse the same Trans. Fluid to Flush it With the Old Transmission Fluid....

[@fixitjohn]

No, I wanted to be done with it. thanks for your comment.

[@giovannibott7242]

Your old oil looks better than knew. That tranny oil is good. Why not replace with Transynd or Torque Drive oil made to Allison Specifications? T668 specifications. Your Allison will love it 👊😎

[@fixitjohn]

Thanks for the tip.

[@ishdhillon4145]

Always use red Allison filter

[@fixitjohn]

Thanks for your comment.

[@white24valve]

Trans pan gasket is reuseable!

[@fixitjohn]

Thanks, that is good to know.

[@white24valve]

I change the spin on filter every 5,000 miles

[@fixitjohn]

That’s great.

[@pennygoodchild2590]

dont use Dex vI in the transmission. bad for seals.

[@fixitjohn]

Hi Penny, That is what the manufacture calls for and that is what I have always run. The transmission has 265000 miles on it and that is including doing heavy hauling and stop-and-go city driving. Thanks for your comment and stay in touch. I value your opinion.

[@white24valve]

No it's not,what it was designed and approved to use..or Allison TES295.

[@ralfie8801]

@@white24valve Allison changed the seals they use in these halfway through the 2006 model year to make them compatible with Dex VI. There’s a serial number breaking point that you use to determine which fluid to use, Dex III before the break and Dex VI after. It’s perfectly fine. The dipstick that Allison provided with mine says to use Dex VI and check it in park.

[@vincerobertson1214]

@@ralfie8801 what year is your truck? I am preparing to drain the tranny fluid from my 2005 Duramax that has 71,000 miles on it. When I bought the truck less than two years ago it had 56,000 miles on it in which I replaced the external spin on filter. The magnet on the spin on filter was completely clean and which I was happy to find the truck has not been used for heavy towing. I will be replacing the external filter again along with the tranny fluid soon. I'm only left to decide which tranny fluid to replace it with. Of course I have researched and I'm leaning toward the delo or the transcind as there are some large truck supply shops near me in the Seattle area. So I am still with the question just so I can be clear... GM brand Dexron type III is what was originally used in this year vehicle? And furthermore that product is no longer available due to licensing constraints? And So the replacement for that ,is now the GM Dexron VI... in which I have learned in your comment above that Dexron VI Is not a recommended for my year of Allison tranny due to non compliance with the seals . I have a lot of notes to write down as I also have a 99 Silverado with a 6.0 that I have to keep the information separate from one another As to not confuse the two Silverado's that I have I just wanna make sure I'm getting it all organized as I go along with servicing both of these vehicles transmissions and fluids including front and rear differentials.

[@lewisgeer1994]

@@ralfie8801 Do you happen to know how to look up the serial number to determine what fluid it should be for a particular truck?