Transfer case needed

[vick214972]

So I have a 1984 k5 blazer, and I have a 5.3 l83 I want to put on. I believe the transmission is a 6l80, my question is what kinda transfer case can I use for that or what would be my best idea?

 

[bucket]

I briefly, half ass researched this at one point. Iirc, you need a special Advance Adapters kit to make the 6L80e work with an older (passenger drop) transfer case.

 

[Camar068]

I briefly, half ass researched this at one point. Iirc, you need a special Advance Adapters kit to make the 6L80e work with an older (passenger drop) transfer case.

I forget who here, but they said that the special adapter wasnt needed.....bolted right up. Said they had done a few.

If it won't bolt up, somewhere here I've got a link to a $120 adapter from Advance Adapters. Good luck finding it on their website, I came across it by luck.

 

[AuroraGirl]

So I have a 1984 k5 blazer, and I have a 5.3 l83 I want to put on. I believe the transmission is a 6l80, my question is what kinda transfer case can I use for that or what would be my best idea?

your alternative is using the trans you have and an adapter for the LS to the trans

 

[RoryH19]

So I have a 1984 k5 blazer, and I have a 5.3 l83 I want to put on. I believe the transmission is a 6l80, my question is what kinda transfer case can I use for that or what would be my best idea?

I used a np241c from a 90-91 Subaru or blazer behind my 4l65e. Bolted in with the factory adaptor. This gives the vss output to the ecu to shift the transmission.

 

[vick214972]

Was it pretty easy to install the whole complete setup? I kinda regret buying the whole setup because I herd it's really expensive, but I really want it on my blazer. Do u have like a fb page where u posted about setups or files about the parts?

 

[shiftpro]

If you could adapt a 32 spline 205 that would be boss. Strong like bull and you can twin shift it. IMO the twin shift is worth the extra weight
and gear noise (music) is relative.... not to mention again but I will... tough company here the 205 is. Availability will be regional.

 

[vick214972]

What about the np208

 

[Bextreme04]

Any transfer case that was originally bolted to a TH400 will bolt right up to a 6L80E. The index ring on the 6L80E is smaller than a TH400 by a few thousandths of an inch, so it will bolt right up with a little bit of free play. They both used a 32 spline shaft and the same 6 bolt pattern.

 

[rpcraft]

The NP208 will need a 32 spline input shaft. I haven't looked but they are usually available about 80 bucks and pretty easy to change out but people have been reporting they are backordered, so YMMV. I think after that my understanding is that if you have a 4x4 6l80E then all you needs is the Tcase adapter you would use for a 6l80E on any of the LS trucks around 2012, and perhaps it is the same as anything previous with a 4l80E. Part #'s should match if so. You end up using 5 out of the 6 bolts which is plenty and It's only around 50 to 50 bucks last time I checked. So far as I know there really isn't any reason to buy one of the "adapter kits" unless you just want to be able to clock the T-case and have money to burn, in which I guess the Advanced Adapter kits are for guys who are afraid to take apart the transfer case and change the input shaft or something? I'm not sure to be honest. I have seen a video where a fellow took a 6l90E 2wd and shortened the shaft and bolted it to the np208 with the adapter from the donor and also seen 4l80e 2wd conversions doing the same. IN order to get digital speed signal from the np208 you will need an output converter from someone like dakota digital, they have 2 units, one is a pass through and VSS, for if you wish to retain your mechanical speedo, and another just does VSS only, and the design behind that is you run the VSS signal to your ECU and then the ECU will output to a speedo that comes from a 1990 to 1991, K5, Burb, or Crew cab (maybe 89 too but I am unsure on that year being included). This fellow is working on a 6l90e conversion to his np208 so perhaps worth a watch, but he seems to be starting with a 2wd transmission. I think if you ask around and do some research and find out what the shaft length difference is between the 2wd and 4wd that will answer the adapter/spacer question.

https://www.youtube.com/c/JEGsGarage/videos

 

[Bextreme04]

If you start with a 2wd 6L80 and cut the shaft, you also need to change the oiling plug to a solid plug from the 2wd one that has an orifice. If you don't do that it will fill the adapter with fluid.

 

[RoryH19]

Was it pretty easy to install the whole complete setup? I kinda regret buying the whole setup because I herd it's really expensive, but I really want it on my blazer. Do u have like a fb page where u posted about setups or files about the parts?

If you are asking me, my build thread is in my signature.
Also there are 2 different outputs for the np241c, a 27 spline and a 32 spline.
I think you will need the 32 version. You can get one from a 90-91 3/4 ton suburban

 

[rpcraft]

If you are asking me, my build thread is in my signature.
Also there are 2 different outputs for the np241c, a 27 spline and a 32 spline.
I think you will need the 32 version. You can get one from a 90-91 3/4 ton suburban

The output depends on what input it originally came with and what transmission was in front of it generally. I’m not aware of the scenario but maybe having a manual transmission can mess with that equation but as far as automatics go generally the 4l60 was a 27 spline and th400 or 4l80ebhadb32 output shaft. You can make it a 32 spline input and retain the 27 spline output if that’s what it started as with just changing the input and not have to change driveshafts and all that stuff.