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Old 03-28-2017, 07:12 AM   #1
Registered User
Join Date: Oct 2016
Location: Martinez,CA
Posts: 48
Th350/np205 help!!!

Hey Guys,
So I just replaced my TH350 with a TCI Unit along with torque converter. This tranny is their truck/4x4 version. I also replaced my tranny mounts on the adapter plate and my Torque mounts on the NP205 with Poly mounts. Tranny runs and shifts as it should. I have new u-joints as well. The flex plate was fine when I installed the tranny. The adapter was also fine and not cracked when I installed it.

The problem is when I come to a stop or stop sign I hear a clunk coming from around my transfer case area or tranny area. It sounds like something is shifting forward. If I put my hand on the 4wd shifter I can feel it happen. There is no play on the drivelines. This has got me completely puzzled on what happened when doing the swap. Is it possible the torque converter or flex plate bolts came loose? and there is play there? How would I know if my adapter plate was now cracked?

Any help with where to start would be great.
mattfrediani is offline   Reply With Quote
Old 03-28-2017, 03:33 PM   #2
Senior Member
Join Date: Feb 2010
Location: Harrah, Washington
Posts: 272
Re: Th350/np205 help!!!

Check the slip yokes on the drive lines. Sometimes they can get a wear "notch" that will produce an audible thump when it slides in and out. When you brake or accelerate these slip yokes need to move.

Hope this helps,

71 Blazer 4X4 (unmolested, all original (including paint) 74,000 mile barn find)
67 Camaro RS SS (unmolested, all original (including paint) 81,000 mile barn find)

Keith Riel
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Old 03-28-2017, 04:43 PM   #3
El Dorado Jim
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Join Date: Dec 2009
Location: El Dorado Ca
Posts: 2,835
Re: Th350/np205 help!!!

this has nothing to do with your noise, but I have read on here that you shouldn't run the torque mounts, they tend to crack trans cases and adapters...the newer trucks that have 205's dont run the braces.....none of my trucks have the braces to the frame,I have 5 trucks with 205's, most of mine dont even have the holes drilled and tapped for the brace
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