C6 fitment question.

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Aug 7, 2011 | 01:55 PM

TYZ78F150

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From: Stafford, VA

C6 fitment question.

I have a 78 F150 4x4, 351M, C6 and NP 205.
I found a petty good deal on a C6 from a 79 F250 with a 400 and NP203. Are there any fitting issues being that it had the 203 and I have the 205, or is it still a bolt in deal?

Aug 7, 2011 | 05:10 PM

Mauch1

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From: Iowa

From the research that i have done on the different transfer cases, if the 203 and the 205 are married units, then they should bolt right up. If you are going from divorced to married or vice versa then you have to change the drive shafts and crossmembers. I am not 100% certain about switching a divorced 205 for a divorced 203 if that will bolt right in or not but from what ive read, the year range of your truck and the truck you are gettin stuff from should have married units. The 203 is considered medium duty while the 205 is considered heavy duty so should be upgrading a bit if they bolt right in.

Aug 7, 2011 | 06:07 PM

TYZ78F150

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From: Stafford, VA

I don't want the 203, I intend to keep my 205, I just want to know if my 205 will bolt up to the tail end of the tranny or not since it had a 203?

Aug 7, 2011 | 07:05 PM

Mauch1

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From: Iowa

Yes it will assuming that both the tcases are married. if the 203 happens to be divorced and your 205 is married then the mounting adapter might be different. But as i stated in my previous post, both the years of your truck and the truck you are taking parts from should have married tcases so going off that info it should bolt right in. Worse case scenerio you might have to change the mounting adapter between the tranny and the tcase because there are different lengths. So if the adapters happen to be different, i think you can just take the one from your old C6 and put it on the other C6 and be sittin good because if you are keepin your 205 then the only thing that is going to matter is the adapter.

Aug 7, 2011 | 08:14 PM

mark a.

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In a married set up, C6's can be short tail or long tail depending on the application. Most if not all 203's I've ever seen were bolted up to the short tail C6. Make sure you get the right one for your truck. I think your truck would have the long tail in it but I'm no half ton expert. The one you are thinking about buying would more than likely be a short tail being it's bolted to a 203

Aug 8, 2011 | 09:52 AM

TYZ78F150

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From: Stafford, VA

So if it is short tail and mine is long, is it just a matter of switching out the tails, or is it a bit more involved than that?

Aug 8, 2011 | 10:21 AM

Joseph69

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The 203 will have a short tail housing /transfer case adapter and shaft the 205 needs a little longer one. The tail housing will swap but the inner shafts are different lengths. The shaft clips in from the inside, so a complete disassembly/rebuild will be needed. Sorry for the bad news.