Automatic Transmission 2-Speed thru 10-Speed GM Autos | Converters | Shift Kits
Sponsored by:
Sponsored by:

need help with th350 diagnosis

Thread Tools
 
Search this Thread
 
Old Jul 13, 2008 | 08:51 PM
  #1  
chad rock's Avatar
Thread Starter
On The Tree
 
Joined: Jun 2006
Posts: 112
Likes: 0
Default need help with th350 diagnosis

I have a built th350 with manual valve body and a transbrake .been doing fine for a couple months. Now when I shift to 2nd its still in first but can shift again and it goes to drive then when you downshift from drive to 2nd it goes in 1st gear .I checked cable and seems like its all working correctly
Reply
Old Jul 13, 2008 | 09:35 PM
  #2  
Johnny@Xtreme_Trans's Avatar
FormerVendor
iTrader: (2)
 
Joined: Jan 2004
Posts: 117
Likes: 0
From: Los Angeles
Default

You probably broke the Intermediate sprag (2nd gear) the th350 weak link. If this is the case then you are going to have to upgrade to 36 element sprag, but to upgrade you have to also have to upgrade the direct drum.
Reply
Old Jul 13, 2008 | 09:40 PM
  #3  
Gilbert@Ace Racing's Avatar
FormerVendor
 
Joined: Oct 2006
Posts: 3,123
Likes: 3
From: D-F/W
Default

Originally Posted by chad rock
I have a built th350 with manual valve body and a transbrake .been doing fine for a couple months. Now when I shift to 2nd its still in first but can shift again and it goes to drive then when you downshift from drive to 2nd it goes in 1st gear .I checked cable and seems like its all working correctly
Sounds like you lost intermediate all together. It could be caused by several different issues. You'll need to disassemble it for inspection.

Did you build it or did a shop? Call that shop if they are local to you, they'll want to see the unit I'm sure. If not, give m a call. We build those frequently.

g
Reply
Old Jul 14, 2008 | 07:29 PM
  #4  
chad rock's Avatar
Thread Starter
On The Tree
 
Joined: Jun 2006
Posts: 112
Likes: 0
Default

thanks for input .a shop built it but not local and it was suppose to have 36 element sprag in the build .they say it has a 6 month warrenty against defects so I gonna give them a call this week.shops in texas im in ms that is a pain in the *** but it wasnt suppose to give me any trouble .oh well if you spray you pay
Reply
Old Jul 22, 2008 | 10:29 PM
  #5  
chad rock's Avatar
Thread Starter
On The Tree
 
Joined: Jun 2006
Posts: 112
Likes: 0
Default

had tranny tore down and it did indeed have a 36 element sprag so shop in texas had good stuff in it.now let me know why it may have broke it. P.S. they are shipping the stuff to fix it
Reply
Old Jul 22, 2008 | 10:36 PM
  #6  
Gilbert@Ace Racing's Avatar
FormerVendor
 
Joined: Oct 2006
Posts: 3,123
Likes: 3
From: D-F/W
Default

I would have to see what failed and know what you were doing when it failed. Sprags are the weak link in these units.

g
Reply
Old Jul 22, 2008 | 10:43 PM
  #7  
dlove's Avatar
TECH Fanatic
iTrader: (23)
 
Joined: Sep 2005
Posts: 1,449
Likes: 1
From: Fort Worth
Default

do you do a 1-2-3 burnout? the shock from the 1-2 to can cause that
Reply
Old Jul 24, 2008 | 09:12 PM
  #8  
chad rock's Avatar
Thread Starter
On The Tree
 
Joined: Jun 2006
Posts: 112
Likes: 0
Default

I do a first second burn out .I have heard not to let tires pull trans down to a stop in 2nd but to acheive that it would have to be more like a rolling burn out without letting off throttle
Reply
LS1 Tech Stories

The Best V8 Stories One Small Block at Time

story-0

Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin

 Verdad Gallardo
story-1

6 Common C5 Corvette Failures and What's Involved In Repairing Them

 Pouria Savadkouei
story-2

Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

 Verdad Gallardo
story-3

Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

 Pouria Savadkouei
story-4

Top 10 Most Powerful Chevy Trucks Ever Made!

 
story-5

Hennessey's New Supercharged Silverado ZR2 Has 700 HP

 Verdad Gallardo
story-6

Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes

 Verdad Gallardo
story-7

Awesome K5 Blazer Restomod Comes With C7 Corvette Power

 Verdad Gallardo
story-8

10 Camaros You Should Never Buy

 
story-9

10 LS Engine Myths That Refuse to Die

 Verdad Gallardo
Old Jul 26, 2008 | 10:34 PM
  #9  
cainsw's Avatar
TECH Resident
20 Year Member
iTrader: (11)
 
Joined: Sep 2002
Posts: 969
Likes: 0
From: Louisiana
Default

I think my trans came from the same shop yours came from in Tx. I just took mine to the track last night for the first time and mine is acting crazy. First off, it will only make it to about 1000ft before it acts like it is slipping at the top of 3rd gear past 5500rpm. Maybe it's the convert? My setup is a cam only 4.30 geared 4000 stall and rmv t brake. I will be calling them Monday and see what they think the problem is. Wasn't trying to hijack your thread, sorry
Reply
Old Jul 27, 2008 | 06:29 AM
  #10  
jay_lt4's Avatar
10 Second Club
iTrader: (4)
 
Joined: Oct 2006
Posts: 855
Likes: 0
From: wisconsin
Default

any pics of the broken 36 element sprag and drum?
Reply




All times are GMT -5. The time now is 07:28 AM.

story-0
Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin

Slideshow: This heavily modified 1971 Camaro mixes classic muscle car styling with a fifth-generation Camaro interior and modern LS3 power.

By Verdad Gallardo | 2026-05-12 18:06:42


VIEW MORE
story-1
6 Common C5 Corvette Failures and What's Involved In Repairing Them

Slideshow: From wobbling harmonic balancers to failed EBCMs, these are the issues that define long-term C5 ownership and what repairs typically involve.

By Pouria Savadkouei | 2026-05-07 18:44:57


VIEW MORE
story-2
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

Slideshow: A modern Camaro transformed into a retro icon, this limited-run "Bandit" build blends nostalgia with brute force in a way few revivals manage.

By Verdad Gallardo | 2026-04-21 13:57:02


VIEW MORE
story-3
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

Slideshow: Cadillac didn't just crash the high-performance luxury vehicle party, it showed up loud, supercharged, and occasionally a little unhinged...

By Pouria Savadkouei | 2026-04-16 10:05:15


VIEW MORE
story-4
Top 10 Most Powerful Chevy Trucks Ever Made!

Slideshow: Top ten most powerful Chevy trucks ever made

By | 2026-03-25 09:22:26


VIEW MORE
story-5
Hennessey's New Supercharged Silverado ZR2 Has 700 HP

Slideshow: Hennessey has turned the Silverado ZR2 into a 700-hp off-road monster with supercharged V8 power and a limited production run.

By Verdad Gallardo | 2026-03-24 18:57:52


VIEW MORE
story-6
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes

Slideshow: A one-off sports car that looks like a vintage Italian exotic-but hides a C6 Corvette underneath-just sold for the price of a new mid-engine Corvette.

By Verdad Gallardo | 2026-03-23 18:53:41


VIEW MORE
story-7
Awesome K5 Blazer Restomod Comes With C7 Corvette Power

Slideshow: A heavily reworked 1972 K5 Blazer swaps its off-road roots for a low-slung street-focused build with modern V8 power.

By Verdad Gallardo | 2026-03-09 18:08:45


VIEW MORE
story-8
10 Camaros You Should Never Buy

Slideshow: There are thousands of used Camaros on the market but we think you should avoid these 10

By | 2026-02-17 17:09:30


VIEW MORE
story-9
10 LS Engine Myths That Refuse to Die

Slideshows: Which one of these myths do you believe?

By Verdad Gallardo | 2026-01-28 18:10:11


VIEW MORE