Transfer Case Crossmembers & Skid Plates

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SamuelB

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Do you know what type of crossmember I would need on a 700r4 (1984 model) trans with transfer, with a tall T case adapter. Truck came with a "w" originally(looks to be modified by previous owner), tranny didn't have transfer beforehand. I'm having trouble mounting it, im not sure if its because the crossmember was modified or if im going to have to use a different style crossmember because of the change of tranny.
 

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Do you know what type of crossmember I would need on a 700r4 (1984 model) trans with transfer, with a tall T case adapter. Truck came with a "w" originally(looks to be modified by previous owner), tranny didn't have transfer beforehand. I'm having trouble mounting it, im not sure if its because the crossmember was modified or if im going to have to use a different style crossmember because of the change of tranny.
84, 700r4 np208. Flat crossmember, tall adapter.

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@HotRodPC is this thread pinned yet? Might be a contender.
i tend to agree. its definitely a wide varietied topic which has insufficient clear-cut answers some of the time because of various combinations and engineering choices
 

HotRodPC

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@HotRodPC is this thread pinned yet? Might be a contender.

Yes, it's a Sticky if that's what you meant by pinned. It's stuck in the top section of the Transmission & Transfer Case > Transfer Case section.

Should be plenty of pics now of all the different Tcase crossmembers. IIRC, there's only 3 and I'm pretty sure I had already posted pics of all 3 and with their correct OEM skidplates too.
 

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Yes, it's a Sticky if that's what you meant by pinned. It's stuck in the top section of the Transmission & Transfer Case > Transfer Case section.

Should be plenty of pics now of all the different Tcase crossmembers. IIRC, there's only 3 and I'm pretty sure I had already posted pics of all 3 and with their correct OEM skidplates too.
I thought there was 4 like the w but one side drops further for an exhaust pipe to pass I think? Maybe im mixing them in my head
 

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There's 5. There's three flatties, a W and an S.
 

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Yes, it's a Sticky if that's what you meant by pinned. It's stuck in the top section of the Transmission & Transfer Case > Transfer Case section.

Should be plenty of pics now of all the different Tcase crossmembers. IIRC, there's only 3 and I'm pretty sure I had already posted pics of all 3 and with their correct OEM skidplates too.

Sorry I didn't check first... admit I thought I should take a peek but I was a slacker. I'll do better next time.
 

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Are one of the flatties you're counting a 1 ton flat compared to the smaller frame rails ones?
I'm lying again cuz I'm forgetting about 1 tons. There is 3 for the 1/2 and 3/4 tons, K5's, Jimmy and Burbs. The 1 tons are taller for the taller frame rail and I'm not certain how many there are for 1 tons.
 

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This is definitely a hot item.Some of those prices on eBay are killer.You would think aftermarket would be on it.W style...

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Curt

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You said modified,how?Most k frames have 4 holes on each side,in 84’ at least.The truck I have had the original flat style that @pariedrifter posted,and now has the w style.The w style bolted right up to the 2 middle holes on each side.I didn’t change transmissions,just transfercase.Because of the minuet differences in overall measements,I did have to use a pry bar to get those holes lined up.The w style was out of an 85’ suburban.The s style would have bolted right up as well,it came later in 86’,I believe.The moderators that posted in this thread have both given detailed info on the gm cross members.

The major differences is the style of trans mount used.84’ and older used the c or u shaped style and then 85 all the way up to the 90s (maybe) used a rectangular block shape looking one.
 

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Are one of the flatties you're counting a 1 ton flat compared to the smaller frame rails ones?

Yes. Although come to think of it, there could be a total of 6 variations. I'm not sure about the 1-tons, but there are two versions of the flat style crossmember. The later ones are a slightly different stamping and have extra holes in the flanges, presumably for skid plates.
 

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I've been following this thread for 2 of my builds. The one I am presently working on is an 87 burb with the 465 and 208 (both factory, talk about a score) I have a host of NP205s laying around and I'm thinking about putting one in this burb.

My question: I have 3 cross members for the NP205 off of 70s pickups (2 are the flat type and one is a w) will they be a direct bolt in for the 87 burb or will some kind of modification be required for install?
 

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I've been following this thread for 2 of my builds. The one I am presently working on is an 87 burb with the 465 and 208 (both factory, talk about a score) I have a host of NP205s laying around and I'm thinking about putting one in this burb.

My question: I have 3 cross members for the NP205 off of 70s pickups (2 are the flat type and one is a w) will they be a direct bolt in for the 87 burb or will some kind of modification be required for install?

The crossmembers are adaper-specific, not case-specific. Your 465 has a 32 spline output and you will need a matching 32 spline 205. Without mixing and matching parts that did not go together in stock form, you will need a round pattern 205 and adapter which will be the short foot style. So in that case, you would just use your stock crossmember that is used with short foot adapters.

Oh and just an FYI to avoid possible confusion in the future, that W crossmember that you pulled off of a 70's truck, it was not original to that truck. It's from an '85 or '86.
 

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