Allison 10L1000 Service Recommendations

[Phishin]

My Silverado 2500 Crew Cab and Long Bed with the 6.6 L8T gasser and 10L1000 transmission is just now at 10,000 miles. I'm want to get ahead of the game before the transmission service is actually needed.

I'm on my 3rd OCI right now (factory fill changed at 2500 miles, and then free dealership change, and now I'm running 5w30 HPL Super Car with Royal Purple filter.

But what is everyone on here recommending for transmission service on these 10L1000 units. Lots of people complaining about these units, I'm thinking it's likely Internet Hype. I know there's a real valve body issue, but not sure how common/prevalent it really is.

Regardless.... I'm looking for advice on what internals to service at, if you guys prefer anything except GM Fluid and Filters, do you recommend fluid exchanges or just pan drops (gets out half the fluid), etc. Thanks in advance for recommendations!!

 

[cpayne5]

I have a nearly identical truck. Mine's a '24 with 12k miles. CCLB, Custom trim, L8T.

There appears to tons of valve body failures with these units on both diesel and gas trucks. The internet always amplifies the negative anecdotes, but I do believe there is a real issue here. So much so that I'm contemplating swapping in a Next Gen valve body as preventative maintenance. Yes, I have a warranty, but I'd rather not roll the dice on being without my truck for a month or more if/when it goes back to the dealer for a valve body.

 

[redhat]

I am in the camp of changing them early and often. I would have not hesitated to do my (albeit a different unit -- 24 Tahoe) 10L80 at 10k, but did mine at 19k. Pan drop, fluid and filter. I also swapped to a PPE pan with a drain plug. I intend upon doing 20k intervals.

I run Dex ULV purely from its price point of under $6 per quart on RockAuto. I'd run HPL but I am doing 20k intervals and fine with that. At 19k, the Dex ULV I drained looked amazing. So I figure every 20k will keep this valve body with nice clean fluid.

That is the big thing I hear about 10L units, aluminum valve body bores with anodized aluminum valves and the dirty fluid accelerates wear on the bores.

 

[clinebarger]

I have a Next Gen kit for my Gen 1 10L80 valve body....The valves are stainless steel & have the highest quality finish I've ever seen, Not to diminish what Sonnax does with anodized aluminum valves.

A clean transmission is a happy transmission...Change the fluid often!

 

[Slick3914]

I am in the camp of changing them early and often. I would have not hesitated to do my (albeit a different unit -- 24 Tahoe) 10L80 at 10k, but did mine at 19k. Pan drop, fluid and filter. I also swapped to a PPE pan with a drain plug. I intend upon doing 20k intervals.

I run Dex ULV purely from its price point of under $6 per quart on RockAuto. I'd run HPL but I am doing 20k intervals and fine with that. At 19k, the Dex ULV I drained looked amazing. So I figure every 20k will keep this valve body with nice clean fluid.

View attachment 306003

That is the big thing I hear about 10L units, aluminum valve body bores with anodized aluminum valves and the dirty fluid accelerates wear on the bores.

That is not the transmission he is asking about.

 

[redhat]

That is not the transmission he is asking about.

Oh maybe you missed my part where I clearly mentioned my acknowledgment of it being a different unit.

Also, perhaps you don’t understand that 10L units share some similar issues regardless of their size/GVWR capacity namely being OE valve body’s needing clean fluid.

 

[nthach]

Looks like you have a cat for quality control, too.

If it was my truck, I’ll stick to my 30K spill and fill and use the “best” Dex-ULV I can afford. These are just an “branded” GM/Ford 10R/Lxxxx series and not a real Allison like in the previous gen GMT/K2XX platform. Isn’t Ford using a slightly tweaked version of this in two ratings(10R100 for the 6.8/7.3L gas and 10R140 for the 6.7L PSD) over on their side?

 

[JavierH19]

Fluid exchanges or multiple pan drops if it's neglected with black fluid which isn't that unit. A spill and fill at a time is all I do. More importantly keep the fluid temps low. I think the thin fluid is fine if it's kept from getting hot.

 

[burbguy82]

I still find is ridiculous that we buy brand new, very expensive cars, knowing of the known issues. This should not even be a thing.

 

[Pablo]

I still find is ridiculous that we buy brand new, very expensive cars, knowing of the known issues. This should not even be a thing.

That applies to lots of things. And what do we get?

Hand waving, lots of magical hand waving.

 

[burbguy82]

That applies to lots of things. And what do we get?

Hand waving, lots of magical hand waving.

unfortunately, we are the only ones to blame

 

[Phishin]

unfortunately, we are the only ones to blame

First off, let's keep it real.

Where I live (NE Indiana), 2500 Silverado's are running all over the road. I don't know if a single 10L1000 issue with any of my friends and coworkers.

Are these transmission issues really going to happen to me? I don't think so. I'm just trying to do what I can maintenance wise to hopefully prevent them from happening and making these issues even less likely to occur.

 

[burbguy82]

First off, let's keep it real.

Where I live (NE Indiana), 2500 Silverado's are running all over the road. I don't know if a single 10L1000 issue with any of my friends and coworkers.

Are these transmission issues really going to happen to me? I don't think so. I'm just trying to do what I can maintenance wise to hopefully prevent them from happening and making these issues even less likely to occur.

I think a pan drop and magnet clean, and filter change is the best and really only option, as far a preventative goes......changing part out just because is another.

Transmission valve bodies are in fact known with this model truck, and TC issues. I had mine for 6 months, and they replaced the valves with another part. At 10000 miles, the magnets were 100% full, and the pan bottom was nasty.

I had 4 post 2020 of these trucks.....al with the 6l90, 1 out of 4 had major issues after15k, yes different transmission, but same thing.........and a 10 speed changes gears more=more clutch pack wear? Maybe.

 

[ls1mike]

First off, let's keep it real.

Where I live (NE Indiana), 2500 Silverado's are running all over the road. I don't know if a single 10L1000 issue with any of my friends and coworkers.

Are these transmission issues really going to happen to me? I don't think so. I'm just trying to do what I can maintenance wise to hopefully prevent them from happening and making these issues even less likely to occur.

Ill be honest and I typically don't listen to internet stuff, I am not sure about this 10 speed valve body. Mine is fine tight now but it is a 24 with 8000 miles on it. It does do some weird stuff

 

[redhat]

The NextGen Drivetrain valve bodies are super nice pieces, but they have a pretty huge price tag.

Additionally, I think GM is now on revision 3 of their valve body that a 10L will get especially when coming in for the recall related to the rear wheel lockup event.

 

[64bawagon]

I think it comes down to how much towing you do. The gasser requires some clearance to drop the pan. Either the transmission mounts need to be loosened and the transmission jacked up and away from the exhaust or the exhaust head pipe needs to be dropped. I do know that Dorman makes a replacement pan with a drain plug and Rock had them for under $200 last I looked.
My plan is to drop my pan at 30k (I use my truck mostly for towing) and do a filter change then. From there I will probably do 20k spill and fills through the new drain plug. Precision makes a decent drain plug that can be added to the pan.
As far as filling it with ULV the fill plug is 18mm pipe thread. I bought a nipple to thread in and then some inexpensive hose to route up to the engine bay. That way I can fill it like a old style unit with a dipstick.

 

[64bawagon]

First off, let's keep it real.

Where I live (NE Indiana), 2500 Silverado's are running all over the road. I don't know if a single 10L1000 issue with any of my friends and coworkers.

Are these transmission issues really going to happen to me? I don't think so. I'm just trying to do what I can maintenance wise to hopefully prevent them from happening and making these issues even less likely to occur.

The volume of repair/service parts needed has affected production to the extent that supply has slowed and Flint rolled back production recently. I would say thats a sign of a problem. Mary does not like it when Flint isnt pumping out their big profit trucks.

 

[4wd]

I am in the camp of changing them early and often. I would have not hesitated to do my (albeit a different unit -- 24 Tahoe) 10L80 at 10k, but did mine at 19k. Pan drop, fluid and filter. I also swapped to a PPE pan with a drain plug. I intend upon doing 20k intervals.

I run Dex ULV purely from its price point of under $6 per quart on RockAuto. I'd run HPL but I am doing 20k intervals and fine with that. At 19k, the Dex ULV I drained looked amazing. So I figure every 20k will keep this valve body with nice clean fluid.

View attachment 306003

That is the big thing I hear about 10L units, aluminum valve body bores with anodized aluminum valves and the dirty fluid accelerates wear on the bores.

Did you have to pull the XO pipe from exhaust ?

 

[4wd]

I think it comes down to how much towing you do. The gasser requires some clearance to drop the pan. Either the transmission mounts need to be loosened and the transmission jacked up and away from the exhaust or the exhaust head pipe needs to be dropped. I do know that Dorman makes a replacement pan with a drain plug and Rock had them for under $200 last I looked.
My plan is to drop my pan at 30k (I use my truck mostly for towing) and do a filter change then. From there I will probably do 20k spill and fills through the new drain plug. Precision makes a decent drain plug that can be added to the pan.
As far as filling it with ULV the fill plug is 18mm pipe thread. I bought a nipple to thread in and then some inexpensive hose to route up to the engine bay. That way I can fill it like an old style unit with a dipstick.

So just X quarts out/X quarts in ?
I hate side fill transmissions - now have 3

 

[Marcozi]

I have a Next Gen kit for my Gen 1 10L80 valve body....The valves are stainless steel & have the highest quality finish I've ever seen, Not to diminish what Sonnax does with anodized aluminum valves.

A clean transmission is a happy transmission...Change the fluid often!

clinebarger to the rescue, as usual!!