The 6L is a great transmission. My 2012 Yukon had 192k on the original transmission when we sold it and it shifted fantastic and had only ever been serviced once by me right after we bought it at 176k. My 2008 has 157k on it now and the new 2013 has 171k both original. My 2008 shifts hard sometimes but they also updated the design of a bunch of the seals in 2009 (I think) and they are better.
6 Speed reliability.
- Thread starter Wylie_Tahoe
- Start date
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Just Fishing
Can't fix stupid
Late 08 they updated the pump stator to use updated sealing rings.
My tahoe is a 09, the transmission was made in late 2008, and it had the updated seals.
It also had the updated piston design in the 1-2-3-4/reverse drum.
Known to crack and loose pressure.
Of course, the updated design is known to crack in new places.
But it's still better than the old one.
I did the billet sonnax while mine was apart.
I also replaced that drum...
That's known to crack around a weld seam.
But of course, this only happens if there is a big pressure spike.
And usually that only happens if the pressure laminates fail, or other pressure regulating things fail.
Me, i replaced a good known drum with a fresh oem one... lol
With my luck and all... haha
But there is this bearing and seal that's pressed into the drum.
I couldn't source the bearing right now, but i could get the drum.
Plus it was the only drum that showed wear where the clutches and steels sit, so i felt like it was the right choice.
Anyways,
These transmissions are great.
I passed on a black ltz that had the 4 speed in favor of the 6.
While i had some issues with my tahoe choice, the 6 speed was the right one.
Also, i always viewed the transmission cooler line filter as "a nice idea" but "not really needed".
My headaches related to converter junk passing through the pump, and then plugging up the transmission cooler has changed my mind on it.
I had 0 clue or signs that there was a restriction.
Maybe the transmission seemed a little warm, but not out of the realm of normal.
Maybe the shifts were a little firmer due to the pressure rise...lol
Yeah, i think all of my vehicles need a cooler line filter adapter now.
6 apeed = fantastic and a delight to work on/rebuild.
From a tuning perspective, you can also play with how fast the clutches retract due to the design.
Each clutch also has a return/off going piston!
Neat stuff!
Down side, you need to do a clutch fast learn if you do major repairs.
Luckily hp tuners can do it.
And a bad tune could cause two opposing clutches to come on at the same time during a shift.
That could be catastrophic.
Older design is a bit forgiving in that aspect.
My tahoe is a 09, the transmission was made in late 2008, and it had the updated seals.
It also had the updated piston design in the 1-2-3-4/reverse drum.
Known to crack and loose pressure.
Of course, the updated design is known to crack in new places.
But it's still better than the old one.
I did the billet sonnax while mine was apart.
I also replaced that drum...
That's known to crack around a weld seam.
But of course, this only happens if there is a big pressure spike.
And usually that only happens if the pressure laminates fail, or other pressure regulating things fail.
Me, i replaced a good known drum with a fresh oem one... lol
With my luck and all... haha
But there is this bearing and seal that's pressed into the drum.
I couldn't source the bearing right now, but i could get the drum.
Plus it was the only drum that showed wear where the clutches and steels sit, so i felt like it was the right choice.
Anyways,
These transmissions are great.
I passed on a black ltz that had the 4 speed in favor of the 6.
While i had some issues with my tahoe choice, the 6 speed was the right one.
Also, i always viewed the transmission cooler line filter as "a nice idea" but "not really needed".
My headaches related to converter junk passing through the pump, and then plugging up the transmission cooler has changed my mind on it.
I had 0 clue or signs that there was a restriction.
Maybe the transmission seemed a little warm, but not out of the realm of normal.
Maybe the shifts were a little firmer due to the pressure rise...lol
Yeah, i think all of my vehicles need a cooler line filter adapter now.
6 apeed = fantastic and a delight to work on/rebuild.
From a tuning perspective, you can also play with how fast the clutches retract due to the design.
Each clutch also has a return/off going piston!
Neat stuff!
Down side, you need to do a clutch fast learn if you do major repairs.
Luckily hp tuners can do it.
And a bad tune could cause two opposing clutches to come on at the same time during a shift.
That could be catastrophic.
Older design is a bit forgiving in that aspect.
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