How many miles did you get out of your original Transmission?
- Thread starter soonrfish
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ktpinnacle
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Truth. I think that the transmission cooling with the trailing package I added when I ordered the rig helped, especially driving through the desert. Minimal trailering and I've babied it for the last 8 years or so. No summer desert runs. Same engine as well, for the same reasons.
swathdiver
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It's not the transmission, it's the thermostat they put on the transmission that keeps it too hot. That and the torque converter's skin is too thin. When it gets hot and flexes, the clutch material goes through the transmission wrecking the pump at minimum.
Marky Dissod
Full Access Member
Fixed it for you.
Even if Dexron6 is well superior to Dexron3, they'll both still perform better and last longer @ 212F
than @ 230F.
Is a 6L90E torque converter a feasible maintenance upgrade here, or is the aftermarket a better bang for the buck?
Depends on who/what you have access to but most competent converter builders will build a much better JMBX (gm code for the 6L80 converter) for $120-150. Add a bunch for a billet cover.
Every transmission type that I have ever worked on runs optimally and lives the longest when temps are kept between 150-190, all other things like keeping up with service intervals, held equal. Dex6 will handle heat better than 3 to a point but heat always "wins" in the end.
For my part, I got nearly 200k out of my 03 Tahoe's original 4L60E before the rear gear train decided to start eating itself on a trip back home from Cali 5 years ago...
the 18th letter
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I've read as much.
swathdiver
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Well, I don't hear about them in having problems in the same way of the JMBX's clutch. They are about 15 pounds heavier and use 6 lugs instead of 3 to bolt to the flex plate.
donjetman
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187k miles on my 2007 6L80 so far.
Changed the torque converter as preventative mx at 130k miles while I was doing the engine rear main seal 4+ yrs ago.
Installed a Precision# P4646 (gopnh.com) converter - $218. Its stronger and for a truck 6L90.
I dump and fill the 6 qts that will come out of the pan every 25k miles and change the filter too every 50k.
I don't tow or hotrod it. I drive conservatively.
Its still going strong.
Changed the torque converter as preventative mx at 130k miles while I was doing the engine rear main seal 4+ yrs ago.
Installed a Precision# P4646 (gopnh.com) converter - $218. Its stronger and for a truck 6L90.
I dump and fill the 6 qts that will come out of the pan every 25k miles and change the filter too every 50k.
I don't tow or hotrod it. I drive conservatively.
Its still going strong.
bobsburban
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Mine made it 272,000 before eating itself for lunch. Installed a Jasper; we shall see.
KraftMatic87
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How’s your Jasper holding up? I just ordered my 6.2 (no AFM) last week and I’ll get my truck back July 21st.
Pyramid_Head
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2011 Suburban 1500 LT here with 123k miles. When I got it, I did a drain and fill. The old oil was dark as hell. Not a good sign. It shifts fine so far though. I'm going to try a drain and fill again and install a new oil strainer and ring seal just in case.
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bobsburban
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Doing fine so far with a bit over 1000 miles on it. Haven't pulled anything yet but that will happen soon as I get some battery and solar mods done on the trailer. After that, I'll change out the fluid and filter at 275,000 along with everything else underneath.
400k.......but it was a 2001 impala 3.8L. Best car I ever owned, then sold and was used, then sold again and was used. Holy crap that thing was bullet proof!
Otherwise I've had good luck with GM fullsize. But all my 6 speeds were either replaced before buying under warranty or had about 160k on them and still worked great. The only wild card is my 8 speed with 136k so far.
Otherwise I've had good luck with GM fullsize. But all my 6 speeds were either replaced before buying under warranty or had about 160k on them and still worked great. The only wild card is my 8 speed with 136k so far.
KraftMatic87
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Nice! We threw a remanned GM torque converter in my factory 6l80 last week it has 145k on it. Fluid and filter looked good when I bought it no metal in the pan and shifts nicely. I had my engine out so I figured we could just throw the new converter in and that might buy me some time. Good luck with your truck!
bobsburban
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Likewise! I'm patiently waiting for the engine to dump itself so I can drop in a non-DOD replacement. It'll probably happen next summer in Nowhere, Nebraska while we're running the Oregon Trail.
ScottyBoy
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Transmission life will depend on several factors, the first being your driving style. If you baby it, of course it will last longer. But if you do a lot more spirited driving with hard launches and acceleration, that will shorten the life.
Towing heavy loads is another major factor that can shorten the life of the transmission. A truck that regularly tows a 6,000 lb boat to the lake every weekend is going to have a LOT more wear and tear than a truck that doesn't tow anything.
Regular transmission fluid changes is yet another factor. If you go over 100k miles without changing the fluid, that's not going to be particularly good for a transmission.
And the number one killer of transmissions is HEAT. If the fluid regularly gets overheated (such as from towing) then that will dramatically shorten the lifespan.
I got just barely over 100k miles out of my 4L60E. I bought my truck at 52k, immediately had the fluid changed. I changed it again at 75 or 80k miles. Then the trans shit the bed at just over 100k miles. But the transmission shop who rebuilt my transmission said it wasn't actually the clutches that wore out. The sun-shell gear broke, and that's what destroyed the transmission. He said if the sunshell has not failed, who knows how many more miles and years I could have gotten out of it.
Towing heavy loads is another major factor that can shorten the life of the transmission. A truck that regularly tows a 6,000 lb boat to the lake every weekend is going to have a LOT more wear and tear than a truck that doesn't tow anything.
Regular transmission fluid changes is yet another factor. If you go over 100k miles without changing the fluid, that's not going to be particularly good for a transmission.
And the number one killer of transmissions is HEAT. If the fluid regularly gets overheated (such as from towing) then that will dramatically shorten the lifespan.
I got just barely over 100k miles out of my 4L60E. I bought my truck at 52k, immediately had the fluid changed. I changed it again at 75 or 80k miles. Then the trans shit the bed at just over 100k miles. But the transmission shop who rebuilt my transmission said it wasn't actually the clutches that wore out. The sun-shell gear broke, and that's what destroyed the transmission. He said if the sunshell has not failed, who knows how many more miles and years I could have gotten out of it.
thats good in general but like you ended with, you have hard parts failing in these trannys. I've kinda followed the threads about the 6L and it seems like it's never the worn out clutches, it's the clutch in the torque converter that's failing most often, which is controlled by the ecm. you can drive it slowly, it will still lock and unlock it often enough to kill it. so you replace it with a billet one with a thicker clutch, but then depending on the year they upgraded a lot of hard parts that fail.
of course not beating on it helps, so does fluid but man they just don't seem to make them like they use to. anything short of fixing all the common design flaws and failure points before they fail. you're not going to drive it till it wears out.
it's a shame.
mine has 150k. I'm the 3rd owner but I believe it's original, nothing on the car fax about tranny. just standard oil changes and stuff, at 10k each ugh way to long for afm haha.
I changed tranny fluid about 135k when I got it. we shall see how it holds up.
it's a 2ML70. so different than most.
I do have a 96 tahoe with a 4l60 with 325k on it. don't know if it's original or not. but I've not changed it, and put a good 150k of that on it myself. over the years when I have it in the shop for oil changes, I've used the oil sucker to drain the pan and refill it with 4qt whatever bulk atf we have laying around. no clue how many times I've done that.
it has had a touch of a delay going into reverse since I got it. I thought for sure I'd be putting a tranny in it. but it's never went out.
I changed tranny fluid about 135k when I got it. we shall see how it holds up.
it's a 2ML70. so different than most.
I do have a 96 tahoe with a 4l60 with 325k on it. don't know if it's original or not. but I've not changed it, and put a good 150k of that on it myself. over the years when I have it in the shop for oil changes, I've used the oil sucker to drain the pan and refill it with 4qt whatever bulk atf we have laying around. no clue how many times I've done that.
it has had a touch of a delay going into reverse since I got it. I thought for sure I'd be putting a tranny in it. but it's never went out.
My 08 has 164k on it now, I thought it was going to need a transmission when I bought it but I changed the filter and reset the adapts and I’m still going 5 years later. My 2012 had 192k on it when we sold it and it shifted beautifully. The 2013 we have now has 180k on it, I thought the torque converter was going but I replaced it and it still feels the same. I might be doing a proactive replacement or rebuild but I’m having fun with my home theater.
