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NP 205 support brace

wazzabie

wazzabie

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From a 72 K5 the NP205 support brace attaches to the frame. One my 78 K5 the NP 203 support strut attaches to the rear of the tranny. Long ago I took out the 78 K5 support strut.

Now I have swapped in a NP205 into the 78 K5.

How important is it that I have the support brace to the frame? The np205 is lighter the then np 203 if I recall.

For those who have done this swap how do you mount the suppor brace to the frame. I placed the old 72 np 205 support brace up to the 78 k5 frame and it does not reach it by an inch or two.

In 77 they went with a wider frame on the K5 or so I have read. I'm just wondering if I could find a frame to tcase support brace for a 77 and up that would work with my 78 K5 with the 72 Np 205 installed.
 
I wouldnt think they would be very important since I have never saw one of the 69-72 side mount's on a 73 up case.All of the post 72's I have saw used the rod going to the bellhousing bolt's.
 
1-tonmudder said:
I wouldnt think they would be very important since I have never saw one of the 69-72 side mount's on a 73 up case.All of the post 72's I have saw used the rod going to the bellhousing bolt's.
Click to expand...

The 73 up had the frame brace. The reason you don't see the brace is because people remove the part when they do tranny work. My 73 had one, but my 74 was missing most of the parts for the brace.
As for wazzabie's problem, I would suggest getting the brace that goes to the motor from an 80s chevy. GM ran NP205s on everything for just for 80, and had the wider frames.
 
tcase.jpg


This is what the older NP 205 brace looks like. The top part mounts to the frame. It falls about 1-2in short of the frame.

I currently have the support stut for the np203 -th350 but it is either to long or short. I don't recall.

What is the advantage/ disadvantage between the motor and frame mount?
 
wazzabie said:
tcase.jpg


This is what the older NP 205 brace looks like. The top part mounts to the frame. It falls about 1-2in short of the frame.

I currently have the support stut for the np203 -th350 but it is either to long or short. I don't recall.

What is the advantage/ disadvantage between the motor and frame mount?
Click to expand...

That's the mount I currently have on my 74. I’ve installed it when I put an NP205 in. (and its off again because I'm swapping a TH400 to replace my blown TH350, but I'm going to put the brace back in when I rebuild my transf . . .
NEVER MIND-MY **** IS BROKEN!)
The NP203 support strut should be longer.
I'm not going to the how and why which is better. Check out the links in my previous post for that debate. I run the frame brace because it's what I have and it fits my application.
 
I prefer the brace between the t/case and the motor.
It keeps the motor/tranny/t-case torquing together as one unit.
The frame brace will secure the t-case to move with the frame flex, and when the motor twists under heavy load, alot of stress is put on the weaker alum tranny case.
Also, GM quit using the older frame brace and went to the newer style motor struts for SOME reason.:thinking:
 
Anybody got pictures of those braces, even better, the braces themselves or what truck they came off of...
 
I had a '73 K10 longbed w/ 465-205 that didn't have the brace. I've never seen them on '73-'80 models.
 
alot of stress is put on the weaker alum tranny case.
Click to expand...

NP203 and NP205's are cast iron. The NP203 does have an aluminum rear differential housing though.

Damn, i should slow down on my reading, you said weaker aluminum tranny case not transfer case. :doah:
 
He doesn't mention which transmission he has, but I was referring to the TH350 or TH400 case.:wink1:
But like you say those are cast iron transfercases, and thats a lot of weight hanging off the back of an aluminium transmission case.

I believe the cast iron 465 manuel tranny does not need the additional support.

brace001.jpg


noahrob,
here is a pic one one of the braces.
There are to more strut braces that go from the inspection cover to the motormounts, but I don't have any pics of them.
 
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I am running a 465/205 setup and the only bracing I have is the cross memeber under the adpter. Sicne the bell housing is aluminum, I am a little concerned, especially since I just busted the adapter...I have the bolt holes on my 205 to attach to the frame but heard that type of bracket transfers a lot of vibration to the driver. I just don't want to fix everything and have it break because I didn't do it right...
 
fatbob said:
He doesn't mention which transmission he has, but I was referring to the TH350 or TH400 case.:wink1:
But like you say those are cast iron transfercases, and thats a lot of weight hanging off the back of an aluminium transmission case.

I believe the cast iron 465 manuel tranny does not need the additional support.

brace001.jpg


noahrob,
here is a pic one one of the braces.
There are to more strut braces that go from the inspection cover to the motormounts, but I don't have any pics of them.
Click to expand...

I'm bringing this thread I started back to life. What is the correct size for the bolt that mount the strut to the tranny? The engine block has a hole that goes all the way thru. Should this be threaded into the block or bolted on the back side with a nut? Also just found out my flywheel cover for the 4x4 is cracked. Argg... I just passed up a nice one at a pull a part a few months ago.
 
wazzabie said:
I'm bringing this thread I started back to life. What is the correct size for the bolt that mount the strut to the tranny? The engine block has a hole that goes all the way thru. Should this be threaded into the block or bolted on the back side with a nut? Also just found out my flywheel cover for the 4x4 is cracked. Argg... I just passed up a nice one at a pull a part a few months ago.
Click to expand...

I will have to check on the bolt, but I know it's the same size as the tranny to engine bolts but a little longer.
As for the cover, I have a couple if you want one PM me so we can take care of it.
 
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