4l80e Question - The 1947 - Present Chevrolet & GMC Truck Message Board Network

67see10 · 09-21-2021, 07:31 PM

Not too familiar with the 4l80e that ran behind a 6.5 diesel but I was wondering it I can use it for a swap.

There's a 01 2wd 4l80e for sale locally and I was trying to determine if it was possible to just switch the tail housing to a regular 2wd TH or would the input shaft will have to be replaced as well?

Attached are some stock photos of a 4l80e that are used behind a 6.5 diesel..

b454rat · 09-21-2021, 07:37 PM

If using it for a 2wd, then cant see why it wouldnt work. Unbolt the brake BS, should be the same. But, never messed with em either....

**Ironangel** · 09-22-2021, 12:19 AM

There is a bolt in the center of the tailshaft yoke, remove it and the six tail housing bolts and the tail housing with brake assembly should slide back and off the tail shaft. The tail shaft lengths are the same. The short tail housing will bolt right on, "however"...You will have to double check the slip yoke end play clearance in relation to u-joint position. In other words, the tail shaft with the bolt on yoke is not clearanced for the longer slip yoke used on Single Rear Wheel axles. There needs to be at least 3/4" end play on the slip yoke to allow the suspension to extend and collapse while maintaining a full bite on the splines. I'm in the middle of this exact swap with a 3L80 (400THM) and a 475THM used in motorhomes and heavy trucks...Pics for reference...The lower tail shaft is the slip yoke shaft, the upper pic is the 475 shaft w/bolt on yoke. Notice the location of the o-ring groove in relation to the splines. Do not cut your slip yoke! Simply have a machine shop bore the end of the slip yoke 1" and your golden...

**kwmech** · 09-22-2021, 01:27 AM

If there is a hole in the end I would look into using a fixed yoke

95 S_Trucker · 09-22-2021, 07:19 AM

That unit is from a C3500HD or P chassis truck. The 1 ton and smaller trucks had a standard slip yoke and tail housing. Because of that parking brake setup, it currently has a fixed yoke.

You can take off all of the brake stuff and use a driveshaft that slips, or swap tail housings and use a slip yoke.

Like previously stated, the output shafts are the same.

09-21-2021, 07:31 PM	#1
67see10 Registered User Join Date: Jul 2017 Location: FL Born, UT Living Posts: 139	4l80e Question Not too familiar with the 4l80e that ran behind a 6.5 diesel but I was wondering it I can use it for a swap. There's a 01 2wd 4l80e for sale locally and I was trying to determine if it was possible to just switch the tail housing to a regular 2wd TH or would the input shaft will have to be replaced as well? Attached are some stock photos of a 4l80e that are used behind a 6.5 diesel.. Attached Images __________________ Instagram: @petestruckfarm

09-21-2021, 07:37 PM	#2
b454rat Senior Member Join Date: May 2004 Location: Binghamton, NY Posts: 3,453	Re: 4l80e Question If using it for a 2wd, then cant see why it wouldnt work. Unbolt the brake BS, should be the same. But, never messed with em either....

09-22-2021, 12:19 AM	#3
Ironangel Senior Member Join Date: Feb 2010 Location: Falls City, Nebraska "100 Miles From Nowhere" Posts: 2,219	Re: 4l80e Question There is a bolt in the center of the tailshaft yoke, remove it and the six tail housing bolts and the tail housing with brake assembly should slide back and off the tail shaft. The tail shaft lengths are the same. The short tail housing will bolt right on, "however"...You will have to double check the slip yoke end play clearance in relation to u-joint position. In other words, the tail shaft with the bolt on yoke is not clearanced for the longer slip yoke used on Single Rear Wheel axles. There needs to be at least 3/4" end play on the slip yoke to allow the suspension to extend and collapse while maintaining a full bite on the splines. I'm in the middle of this exact swap with a 3L80 (400THM) and a 475THM used in motorhomes and heavy trucks...Pics for reference...The lower tail shaft is the slip yoke shaft, the upper pic is the 475 shaft w/bolt on yoke. Notice the location of the o-ring groove in relation to the splines. Do not cut your slip yoke! Simply have a machine shop bore the end of the slip yoke 1" and your golden... Attached Images __________________ Michael of the clan Hill, "Two Seventy Two's" 71 1-ton Dually 350 4-Speed 71 C/50 Grain Truck, 350 Split-Axle 4-Speed 02 3/4 ton Express 14 Indian Chief Vintage 1952 Ford 8N, "Only Ford Allowed On The Property" "Be American, Buy American" Last edited by Ironangel; 09-22-2021 at 12:35 AM.

09-22-2021, 01:27 AM	#4
kwmech Senior Member Join Date: Mar 2003 Location: Colfax-California Posts: 8,389	Re: 4l80e Question If there is a hole in the end I would look into using a fixed yoke

09-22-2021, 07:19 AM	#5
95 S_Trucker Registered User Join Date: Oct 2009 Location: . Posts: 2,178	Re: 4l80e Question That unit is from a C3500HD or P chassis truck. The 1 ton and smaller trucks had a standard slip yoke and tail housing. Because of that parking brake setup, it currently has a fixed yoke. You can take off all of the brake stuff and use a driveshaft that slips, or swap tail housings and use a slip yoke. Like previously stated, the output shafts are the same.



Register or Log In To remove these advertisements.

Register or Log In To remove these advertisements.