4L80E w/241 - The 1947 - Present Chevrolet & GMC Truck Message Board Network

Sir Fisher · 12-01-2007, 12:51 AM

hey guys, i have a 4L80E that i would like to hook up to a np241. i don't know much about this whole t-case stuff so i need your help.
1. does the np241 have the output shaft on the passenger side?? because that's what i need.
2. do i need an adapter to connect them together?? where can i find one if i need it?? i didn't see anything on the advance adapter page.
3. what are you guys talking about when you're refering to the splines?? how do i know what i have and what i need.
4. or would a different t-case be better fit for what i'm trying to do??

i searched the archives, but haven't found much info... maybe i don't know what to search for. any help is greatly appreciated!!

thanks much!!

earl87gta · 12-01-2007, 04:27 AM

you need to find a 241 out of an 80s modle3/4 or 1ton truck or early 90s modle 1ton truck with the 400 trans in it. Alot of the diesel trucks had them in it. no adaptors needed the 400 and the 4l80e had 32 spline trans and the 241 with the 400 had the round bolt patern needed to use the the 4l80e trans. just make sure it came out of a truck with a strait axle under it and it will be passenger drop. you other option would be a np205 out of a later modle 1ton truck you will need the one with the round boult pattern for the trans and look at spending big money there hard to get you hands on to. look around for some one parting out a m1008 for the axles and see if you can get the transfercase.

**special-K** · 12-01-2007, 07:24 AM

The last solid axle Blazers and Suburbans (88-91) came with passenger-drop NP241s.I`m not sure how early they switched from The NP208.All these transfer cases have the same mating area.I have a`91 3/4t Suburban with the 4L80E/NP241.That was the first year 3/4t Suburbans were available with o/d.The 700r4 will bolt to whatever the 4L80E will and was used widely.

earl87gta · 12-01-2007, 09:32 AM

700r4 has a 27 spline output shaft the the 4l80e has a 32 spline so the needs one from a truck with ether a 400 trans or a 4l80e. the 208 is another option you could look in to and should be able to get cheap.

Sir Fisher · 12-02-2007, 08:28 PM

very cool guys, thanks for the info!! getting one step closer to starting my build.

**kwmech** · 12-02-2007, 09:39 PM

Parts are factory if you can find a 91 3/4 ton 'burb

bigtruck81 · 12-04-2007, 12:36 AM

take you 241 and swap a 32 spline into it, much easier than finding the uber rare cases these guys are telling you to find.

BTW, straight axle 88 and 89 had 241s with mechanical speedos, 90 and 91 were electrical.

12-01-2007, 12:51 AM	#1
Sir Fisher Registered User Join Date: Sep 2007 Location: West Coast FL Posts: 204	4L80E w/241 hey guys, i have a 4L80E that i would like to hook up to a np241. i don't know much about this whole t-case stuff so i need your help. 1. does the np241 have the output shaft on the passenger side?? because that's what i need. 2. do i need an adapter to connect them together?? where can i find one if i need it?? i didn't see anything on the advance adapter page. 3. what are you guys talking about when you're refering to the splines?? how do i know what i have and what i need. 4. or would a different t-case be better fit for what i'm trying to do?? i searched the archives, but haven't found much info... maybe i don't know what to search for. any help is greatly appreciated!! thanks much!! __________________ 1970 Chevy K20 Custom Camper 1996 Chevy Impala SS 2008 Chevy Avalanche LT3 2003 Honda Accord EX 2001 Hewes Redfisher 16 Fighting Lady Yellow Build thread: http://67-72chevytrucks.com/vboard/s...d.php?t=324118

12-01-2007, 04:27 AM	#2
earl87gta Senior Member Join Date: Dec 2003 Location: Kingsport TN Posts: 4,641	Re: 4L80E w/241 you need to find a 241 out of an 80s modle3/4 or 1ton truck or early 90s modle 1ton truck with the 400 trans in it. Alot of the diesel trucks had them in it. no adaptors needed the 400 and the 4l80e had 32 spline trans and the 241 with the 400 had the round bolt patern needed to use the the 4l80e trans. just make sure it came out of a truck with a strait axle under it and it will be passenger drop. you other option would be a np205 out of a later modle 1ton truck you will need the one with the round boult pattern for the trans and look at spending big money there hard to get you hands on to. look around for some one parting out a m1008 for the axles and see if you can get the transfercase. __________________ Earl 68 2500 4x4 GMC Burb Last edited by earl87gta; 12-01-2007 at 04:31 AM.

12-01-2007, 07:24 AM	#3
special-K Special Order Join Date: Nov 2004 Location: Mt Airy, MD Posts: 85,862	Re: 4L80E w/241 The last solid axle Blazers and Suburbans (88-91) came with passenger-drop NP241s.I`m not sure how early they switched from The NP208.All these transfer cases have the same mating area.I have a`91 3/4t Suburban with the 4L80E/NP241.That was the first year 3/4t Suburbans were available with o/d.The 700r4 will bolt to whatever the 4L80E will and was used widely. __________________ "BUILDING A BETTER WAY TO SERVE THE USA"......67/72......"The New Breed" GMC '67 C1500 Wideside Super Custom SWB: 327/M22/3.42 posi.........."The '67" (project) GMC '72 K2500 Wideside Sierra Custom Camper: 350/TH350/4.10 Power-Lok..."The '72" (rolling) Tim "Don't call me a redneck. I'm a rough cut country gentleman" R.I.P. ~ East Side Low Life ~ El Jay ~ 72BLUZ ~ Fasteddie69 ~ Ron586 ~ 67ChevyRedneck ~ Grumpy Old Man ~

12-01-2007, 09:32 AM	#4
earl87gta Senior Member Join Date: Dec 2003 Location: Kingsport TN Posts: 4,641	Re: 4L80E w/241 700r4 has a 27 spline output shaft the the 4l80e has a 32 spline so the needs one from a truck with ether a 400 trans or a 4l80e. the 208 is another option you could look in to and should be able to get cheap. __________________ Earl 68 2500 4x4 GMC Burb

12-02-2007, 08:28 PM	#5
Sir Fisher Registered User Join Date: Sep 2007 Location: West Coast FL Posts: 204	Re: 4L80E w/241 very cool guys, thanks for the info!! getting one step closer to starting my build. __________________ 1970 Chevy K20 Custom Camper 1996 Chevy Impala SS 2008 Chevy Avalanche LT3 2003 Honda Accord EX 2001 Hewes Redfisher 16 Fighting Lady Yellow Build thread: http://67-72chevytrucks.com/vboard/s...d.php?t=324118

12-02-2007, 09:39 PM	#6
kwmech Senior Member Join Date: Mar 2003 Location: Colfax-California Posts: 8,463	Re: 4L80E w/241 Parts are factory if you can find a 91 3/4 ton 'burb

12-04-2007, 12:36 AM	#7
bigtruck81 Registered User Join Date: Feb 2004 Location: northern, in Posts: 350	Re: 4L80E w/241 take you 241 and swap a 32 spline into it, much easier than finding the uber rare cases these guys are telling you to find. BTW, straight axle 88 and 89 had 241s with mechanical speedos, 90 and 91 were electrical.



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