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Discussion Starter #1
I’ve noticed a few spots in the drive way about 5-6 inches in diameter today . I crawled underneath and it appears that my transmission pan is leaking at the back corner . Just want to make sure I’m ordering everything I need. I was just going to order this kit
https://www.merchant-automotive.com/10020-Allison-Deep-Pan-Transynd-Filter-Lock.aspx?pid=7523&gclid=Cj0KCQjw5rbsBRCFARIsAGEYRwfjiiZsWrpAtKfuVJkvrbxLRdFZH4VaZo-0RSxX1fruzqS1BtUlhEEaAgVGEALw_wcB

Plus a new gasket for the pan . Please let me know if there’s anything I’m missing . Also would now be the time I should add transgo kit . and do I really need a new pan , or would just ordering a gasket work ?
 

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Real silly question here but did you try and tighten the bolts?
Unless you see visible damage, I don’t see the need for a new pan.

The gasket should be reusable unless it has been tweaked last time it was put on. I’m not sure what trans fluid that is but I’d go with at least a Mobil Delvac TES-295 full synthetic. Could be wrong here-May HAVE to go with dex6 but maybe someone can chime in.
 

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Discussion Starter #3
Real silly question here but did you try and tighten the bolts?
Unless you see visible damage, I don’t see the need for a new pan.

The gasket should be reusable unless it has been tweaked last time it was put on. I’m not sure what trans fluid that is but I’d go with at least a Mobil Delvac TES-295 full synthetic. Could be wrong here-May HAVE to go with dex6 but maybe someone can chime in.
Here’s the weird thing , it randomly just started to leak . Actually the i just had the truck at a shop where they cleaned the frame and painted it with chassis saver . When I got the truck back I noticed they painted my tranny too. They painted right over the spin on filter and over the filter pan .. I was able to bust the spin on filter loose , but had them check and make sure I could get the pan off when I wanted to . They took it in their shop and told me they had the guy wipe it down with a solvent “no lacquer “ and he said there’s no way they could have damaged my gasket . Well maybe it’s a coincidence , but two weeks later and it’s leaking fluid
 

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Id pull the main harness plug and verify its not leaking through the wires and then down the pan, making it look like a pan gasket leak.

My 06 leaked from the plug so swapped out the main harness and now I'm good to go.

Sent from my VS988 using Tapatalk
 

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Real silly question here but did you try and tighten the bolts?
Unless you see visible damage, I don’t see the need for a new pan.

The gasket should be reusable unless it has been tweaked last time it was put on. I’m not sure what trans fluid that is but I’d go with at least a Mobil Delvac TES-295 full synthetic. Could be wrong here-May HAVE to go with dex6 but maybe someone can chime in.
If his transmission takes Dex 6 he can use any TES-295 fluid but should do the double drain to change it out.
 
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Check everything mentioned above before you drop your pan.

The small cost for a new gasket if you drop the pan, is nowhere near the cost of fluid if you end up with another leak.
Mine after only about 40k miles after I did the transgo jr and deep pan, the gasket didn’t look all that good to think about re-using.
I changed my lines because of leaks at the fittings and decided to pull the pan to inspect after hotter than normal trans temps.

Depending on how old your fluid is and how many miles is on it, instead of having that costly fluid waist doing the double drain method, you can get the front up at least 6” higher than the rear and let it set a couple of days allowing the fluid to drain down from the lines and converter, then remove the plug and pan if your replacing anything.
While your at it replace the internal filter, these lifetime internal filter claims have been flushed down the toilet.
It’s now around the 100k miles suggestion per real live Allison service people.
When I do the method I’m suggesting above, I’ll drain out about 13 1/2 quarts with a normal 9 1/2 quart change when your just draining and refilling.
 

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Discussion Starter #8
Real silly question here but did you try and tighten the bolts?
Unless you see visible damage, I don’t see the need for a new pan.

The gasket should be reusable unless it has been tweaked last time it was put on. I’m not sure what trans fluid that is but I’d go with at least a Mobil Delvac TES-295 full synthetic. Could be wrong here-May HAVE to go with dex6 but maybe someone can chime in.
The fluid with the kit is 3 gallons of transynd . You think I should have to tighten the bolts? I’m just not sure how they would have come loose without being touched
 

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Discussion Starter #9
Id pull the main harness plug and verify its not leaking through the wires and then down the pan, making it look like a pan gasket leak.

My 06 leaked from the plug so swapped out the main harness and now I'm good to go.

Sent from my VS988 using Tapatalk
I looked at the pan and felt around it’s not wet anywhere that I can tell except where the pan meets the tranny . Is the harness still a possible culprit ? I’m not that familiar with these trannys
 

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Discussion Starter #10
Real silly question here but did you try and tighten the bolts?
Unless you see visible damage, I don’t see the need for a new pan.

The gasket should be reusable unless it has been tweaked last time it was put on. I’m not sure what trans fluid that is but I’d go with at least a Mobil Delvac TES-295 full synthetic. Could be wrong here-May HAVE to go with dex6 but maybe someone can chime in.
If his transmission takes Dex 6 he can use any TES-295 fluid but should do the double drain to change it out.
I was gonna go with transynd . I just bought the truck 2 months ago . Can I ask the reason for a double flush ?
 

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Discussion Starter #11
Check everything mentioned above before you drop your pan.

The small cost for a new gasket if you drop the pan, is nowhere near the cost of fluid if you end up with another leak.
Mine after only about 40k miles after I did the transgo jr and deep pan, the gasket didn’t look all that good to think about re-using.
I changed my lines because of leaks at the fittings and decided to pull the pan to inspect after hotter than normal trans temps.

Depending on how old your fluid is and how many miles is on it, instead of having that costly fluid waist doing the double drain method, you can get the front up at least 6” higher than the rear and let it set a couple of days allowing the fluid to drain down from the lines and converter, then remove the plug and pan if your replacing anything.
While your at it replace the internal filter, these lifetime internal filter claims have been flushed down the toilet.
It’s now around the 100k miles suggestion per real live Allison service people.
When I do the method I’m suggesting above, I’ll drain out about 13 1/2 quarts with a normal 9 1/2 quart change when your just draining and refilling.
Great advice , I will check all these spots in the morning . What is the reason for double flushing ? Will it hurt if transynd and oem fluid mix ?
 

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To try to get out as much old fluid you can, a few has said you might get about 85%-90% changing the double drain method.
What I started doing after flushing about $120 down the toilet using transynd doing the double drain, I let my truck set for a couple of days up on 6” blocks, then removed the drain plug measured getting out 13 1/2 quarts, with the Allison deep pan, which should be around 75%, I had just did a drain and re-fill.

Drain your fluid into a measuring bucket, (pictured below) then you won’t have to be worried on how much to put back in.
As long as the Dex 6 is in decent shape with a pretty red color, I don’t think it’d be a problem.
If it’s pretty crappy and burnt, then maybe the double might be better choice.

Mines been changed 3 times (dropping the pan, not counting my double drain)
and I only have 84k miles, the inside of the pan and fluid has always looked very good.
 

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The double drain method pretty much ensures most of not all of the old fluid is removed. Especially if you change from dex6 to TES295. Fluids of today-especially synthetics are much better at high pressure high demand applications. If this is the first time you have changed the fluid then do the double drain and have peace of mind.
 

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Here’s a no brainer suggestion.
If your pulling the pan, you really don’t have to worry about the double method.
If your just draining the fluid let it set on blocks for a couple of days if you can, even one day would help.
Drain and re-fill measuring what you got out.

Then drive it for, some say 50 miles some say a couple hundred miles before you do the second drain, to give the fluid a chance to blend together, me personally I don’t think it would take 25-30 miles.

Then you make the call on the second drain.
This is not one of those “Wham Bam Double Drain” instantly things.
 

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A friend of mine did his by disconnecting a line from the transmission cooler. Had the 5 gallon bucket up haughty and a tube going into filler. Would crank his truck a let it go till the stuff coming out of the cooler was fresh. Hooked his cooler up, and topped it off.
 

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A friend of mine did his by disconnecting a line from the transmission cooler. Had the 5 gallon bucket up haughty and a tube going into filler. Would crank his truck a let it go till the stuff coming out of the cooler was fresh. Hooked his cooler up, and topped it off.
Personally I thin he may ve a friend of yours, but he was NO friend to his transmission!
 
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If your goin to be crazy enough to do the hoot method, you really should have 2 people doing this.
Being crazy enough to do this by yourself there’s a good chance you’ll be a little slow watching the fluid to change colors then running back to your cab (probably tripping) to turn off the key, toasting your transmission during the process.
 

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A friend of mine did his by disconnecting a line from the transmission cooler. Had the 5 gallon bucket up haughty and a tube going into filler. Would crank his truck a let it go till the stuff coming out of the cooler was fresh. Hooked his cooler up, and topped it off.
Would your buddy change his engine oil like this?

Ahhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh............no

(.....or maybe he would! )
 
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