Info: 4l80e behind a Duramax

[MAXX IT OUT]

I am going to put a 4l80e in my C10 and hopefully next year my spare duramax engine will follow. I know the 4l85e was behind the LBZ, but does it require a different flywheel and converter over normal duramax flywheel and 4l80e converter. What are the MUSTS mods that need to be done to handle any torque. I am planning on running some sort of controller with paddle shifter. Any ideas or though?

 

[malibu795]

Get the Allison flex plate I ripped the oem4l85 flex plate 6bolts holes direct bolt in.. Get lower bell housing brace..
JoshH has a list somewhere of everything he did in his van... How much power do you plan on running

 

[MAXX IT OUT]

500hp in a 4500 pounds truck should be enough, plus then I don't have to get fancy with engine.

 

[MAXX IT OUT]

What do you mean by lower bell housing brace

 

[Turbo Performance]

You don't have to change flywheel from stock Dmax and a normal 4L80 converter will bolt up.

 

[MAXX IT OUT]

What hard parts need to be upgraded Levi? How is it doing over for you. What are you running for a controller?

 

[malibu795]

OEM dmax/4l85 flex plate and what I did to it.

Lower bell housing brace

 

[MAXX IT OUT]

Is that the same as the dmax/allison plate? How long did that flex plate last?

 

[malibu795]

Is that the same as the dmax/allison plate? How long did that flex plate last?

No sir 4l80 and alision flex plate are different bolts holes are the same and mounting faces are the same.. The plate is also thinker on the Allison as well

 

[Turbo Performance]

What hard parts need to be upgraded Levi? How is it doing over for you. What are you running for a controller?

I'd bet I'm lighter than you'll be by a good bit. I'm around 3500lbs fwiw. I was only making 400ish hp with my turbine housings being too big but the trans I'm running is bone stock. Didn't do anymore than change the fluid and stuff it in. Even stock converter. Wanted to find the breaking point but haven't got there yet. Probably had around 9K miles and 50ish passes this summer without issue. From my research, clutches and a billet input will hold some decently serious power so that's my plan this winter.

Also, I don't have a controller on my trans, I built brackets inside the shifter housing for micro switches to activate the right solenoid(s) for each gear. Probably get a lot of turned up noses for that but it was cheap, effective and it's been trouble free.

OEM dmax/4l85 flex plate and what I did to it.

Lower bell housing brace

I'm curious to the context this was broken? What weight was the vehicle or trailer and how much power? Easy to post broken parts and say to get different or upgraded ones but it's more helpful to give the conditions and information on how it happened to make the choice.

 

[MAXX IT OUT]

I'd bet I'm lighter than you'll be by a good bit. I'm around 3500lbs fwiw. I was only making 400ish hp with my turbine housings being too big but the trans I'm running is bone stock. Didn't do anymore than change the fluid and stuff it in. Even stock converter. Wanted to find the breaking point but haven't got there yet. Probably had around 9K miles and 50ish passes this summer without issue. From my research, clutches and a billet input will hold some decently serious power so that's my plan this winter.

Also, I don't have a controller on my trans, I built brackets inside the shifter housing for micro switches to activate the right solenoid(s) for each gear. Probably get a lot of turned up noses for that but it was cheap, effective and it's been trouble free.



I'm curious to the context this was broken? What weight was the vehicle or trailer and how much power? Easy to post broken parts and say to get different or upgraded ones but it's more helpful to give the conditions and information on how it happened to make the choice.

Could you post some pictures of your set up....i want to keep as cheap as possible so I can get it running.

 

[Mike L.]

The 4L80E, just like the Turbo 400 has a lot of case flex. They like to break the case just behind the bell housing. The lower converter cover acts like a girdle. Use real good mounts. Aluminum pan would help. It doesn't have to be a deep one.

 

[malibu795]

I'm curious to the context this was broken? What weight was the vehicle or trailer and how much power? Easy to post broken parts and say to get different or upgraded ones but it's more helpful to give the conditions and information on how it happened to make the choice.

In my red dually lbz/4l85 ~275fwhp. Grossing ~24,000lb I replaced it with a lbz/Allison flex plate which is also thicker than the 4l85 flex plate.. This is the one on my LMM

 

[Turbo Performance]

Not sure how much it'll help but here's a picture of the 3 micro switches I put in my shifter housing. The shift solenoids ground through the micro switches so when the shifter mechanism hits the micro switch, it grounds the correct solenoid for the desired gear. It works just fine and I didn't have to buy a manual VB to get what I wanted. Apparently you can pull the pan, re-wire the pressure manifold and solenoids a certain way to get full manual operation too. I originally did that but never got it to work as advertised so I went the next cheapest/easiest way with the micro switches on the shifter. I can give you all the info on the wiring setup that I gathered if you want. Just don't want to dive into it here if no one needs it.

 

[malibu795]

Nicely done Levi. I wouldn't mind havih a wiring schematic to have on file for later date.. I have a 4l85 waintjng to go in a vehicle.

 

[MAXX IT OUT]

Nicely done Levi. I wouldn't mind havih a wiring schematic to have on file for later date.. I have a 4l85 waintjng to go in a vehicle.

I am looking for one, if the price isn't threw the roof. Buy the 4l80 is easier to lay hands on.

 

[JoshH]

I have 3 years and a few hundred passes on it without any hard part failures. The first builder couldn't figure out how to get the clutches to hold up, but since I went through it myself and put a valve body from Rossler in it, it has been flawless for 2 years. Lots of mid 11 to very low 12 second passes on fuel only, and 1 10 second pass and a few low 11 second passes spraying nitrous.

 

[Turbo Performance]

Nicely done Levi. I wouldn't mind havih a wiring schematic to have on file for later date.. I have a 4l85 waintjng to go in a vehicle.

Thanks. I'll post up some of the wiring info on the solenoids and manual operation tomorrow when I get back in the shop. Real simple stuff. Think I have it for both the 4l80 and 4l85 if memory serves since I was actively looking for an 85 until I stumbled onto cheap 4l80's and my wallet made the decision.

I have 3 years and a few hundred passes on it without any hard part failures. The first builder couldn't figure out how to get the clutches to hold up, but since I went through it myself and put a valve body from Rossler in it, it has been flawless for 2 years. Lots of mid 11 to very low 12 second passes on fuel only, and 1 10 second pass and a few low 11 second passes spraying nitrous.

This on a 4L80 Josh? Any hard parts upgrades? Input, output, or just clutches and VB?