Limped the Trans on the LLY

Jake707

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Mar 30, 2020
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Well it happened. I have been running the level 4 performance tune on the CTS2 on my 05 lly and was running a dump trailer, not too heavy maybe 3k lbs or so and getting on the freeway it slipped and went to 4th gear only limp mode.

I erased the code and put it on 3 the towing tune instead and it seems to be running fine right now but from what I read once limped from slipping it will continue to get worse?

What are my options? Sure one would be drop the truck off with a blank check and call it a day but the way my bank account is set up....... haha

Can I rebuild it myself? Is there a strong kit that would be an upgrade that I can do myself on a weekend? I’ve rebuilt so motors etc before so not totally a newbie but will not assume to know how an auto trans works either so research would still be needed.

Just looking for advice now before it becomes a problem so I can start planning it out.
 

Mike L.

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" Before it becomes a problem" ?
You need a trans rebuild. Be carefull who you use or you will do it again. Can you do it? Who knows.
 

Jake707

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Mar 30, 2020
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I’d call it an issue not a problem just yet haha.
So you’re saying it’s not your average DIY type project then.
 

TheBac

Why do I keep doing this?
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Apr 19, 2008
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Put the CTS back to level 1 or leave it stock, esp when pulling your trailer. You didnt listen to the advice in your intro thread, eh?


Contact Evan at Elevated Ingenuity for a rebuild kit. You can do it, but you better read up on your Allison manuals and ATSG book first.
 

Bdsankey

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You are at the time to rebuild the trans. Put the tuner back down to the lowest setting and keep it there. Rebuilding a trans is time-consuming and has a lot of little nuances that must go back together in the proper order for them to function correctly and receive the desired result.

I can get you set up with a kit but would recommend taking it to an experienced builder. You then get peace of mind knowing its done right and a warranty that someone can actually stand behind.
 

Evan@InglewoodTrans

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If you’re mechanically inclined and take things serious during the build it’s more then doable for the do it yourselfers out there. The only time I’ve had kit customers have an issue is when they don’t ask questions when they aren’t sure on something. I encourage questions and nobody has to be embarrassed to ask them because they don’t know...I don’t expect them to just like there was a time I didn’t know either. Over the last few days I’ve been rewriting our instructions and revising the kits to make things even better for customers.
 
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NC-smokinlmm

<<<Future tuna killer
May 29, 2011
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Good advise Evan. Reminds me of something I heard a mate say to a captain once. "How am I supposed to know things I don't know captain?"

Everyone has been a novice at EVERYTHING...
 

WolfLMM

Making Chips
Nov 21, 2006
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Evan sells a good kit with everything you need minus a couple of special tools. I built mine with one of his kits. Only advice I have is; have a large uncluttered and CLEAN work area. Clean everything twice and then again cause you didn’t clean it enough yet.
 

Jake707

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Mar 30, 2020
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Thanks all. Looks like kit prices can be all over the place. Some for $1200 and some coat more than an average rebuilt by a shop. I guess different components really come into play.

Anyone know if there is any specialty tools and/or electronics I would need to tackle this?
 

zakkb787

<that’s not me...
Sep 29, 2014
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An Allison trans is not something to cheap out on. Kit or builder. That $1,000 savings now could cost you $3,000 later. My advice if you’re wanting to do it yourself is give Evan a call. Buy his kit. And it will come with all the components and professional advice you’ll need. Otherwise, buy a trans from Evan, Mike, or one of the vendors here that know what they’re doing. There’s a reason these guys are allowed to sell here. Because they’re stand up guys. And know what they’re doing with the products they sell. Even if you do get a trans built by someone with a sub-par kit and it feels okay at your current power level, it might not live with 100 more hp or last 30k miles. Or it might be great. But do you really want to gamble with those odds lol
 

Mike L.

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So called kits rarely fit properly and are only clutch and Trango kits. The sellers have no idea how a Allison works and just want the money. Buy Evans kit.
 

Jake707

Member
Mar 30, 2020
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No I’m def not looking to skimp. If I tackle this it’s going to be a do it once and done I was just shocked at the price differences.
 

Jake707

Member
Mar 30, 2020
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Another question
Are all year 5 speeds compatible? Meaning would an 03 LB7 Allison work on my LLY? I know the 6 speeds aren’t due to computer programming etc from what I read. I’m looking at possibly buying one from a salvage yard and rebuilding that if I can get one cheap.
 

Burn Down

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Sep 14, 2008
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Valve bodies, harness and trans cooler fittings are different between lb7 and lly. You can use any Allison from 01-10 not sure if a lml can be adapted or not? Evan or Mike would know.
 

Bdsankey

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Valve bodies, harness and trans cooler fittings are different between lb7 and lly. You can use any Allison from 01-10 not sure if a lml can be adapted or not? Evan or Mike would know.

It would depend on the year/generation of the trans. There was the early or late 5spd. Early LB7 didn't have the g-trim solenoid and they also had different size cooler fittings/lines. Late LB7 and LLY share the same trans. With that said, there are adapter fittings available from GM to put either trans into either generation (late into early and early into late). If your trans is not equipped with a g-trim solenoid you would need to swap valve bodies and harnesses to regain that functionality and to make the TMC happy.
 
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Mike L.

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LLY valve body will need the G solenoid as the TCM will be looking for it and '03 doesn't have it. Valve body will interchange along with matching harness '03 had a cooler fitting change in mid year. GM has the interchange fittings so it can easily be done.
 

Jake707

Member
Mar 30, 2020
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Right on fellas. Just trying to get as much info as possible before deciding which route to take.
 

Burn Down

Hotrodder
Sep 14, 2008
7,092
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48
Boise Idaho
It would depend on the year/generation of the trans. There was the early or late 5spd. Early LB7 didn't have the g-trim solenoid and they also had different size cooler fittings/lines. Late LB7 and LLY share the same trans. With that said, there are adapter fittings available from GM to put either trans into either generation (late into early and early into late). If your trans is not equipped with a g-trim solenoid you would need to swap valve bodies and harnesses to regain that functionality and to make the TMC happy.

Did you not read my post? I said valve body, harness, trans cooler fittings. Been there done that 9 years ago.

Iirc the bell housing thread sizes are different for those cooler fittings as well. I deleted my factory lines and went full braided cat hose and jic fittings.