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Old 03-05-2010, 11:12 PM   #1
LongSixEight
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What happened to my trans???

Trans is a fresh rebuild with a tran-go manual valve body and a tci 3000conv. I went out and played a little and everything worked flawless. The truck sat for a week and has no first gear and drive feels like its bound up and bogging the motor down. I checked the shift arm on the trans with the shifter. Everything is right where it needs to be when shifted. Any ideas
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Old 03-05-2010, 11:37 PM   #2
cableguy0
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Re: What happened to my trans???

Is it making any noise? While you were out driving did you downshift into first gear without first coming to a stop?
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Old 03-05-2010, 11:44 PM   #3
LongSixEight
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Re: What happened to my trans???

Thats strange you ask that. I actually did going around 20mph or so on accident. Could that have hurt it? There are no noises or vibrations.
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Old 03-06-2010, 02:59 AM   #4
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Re: What happened to my trans???

There should be a big warning on the manual valve bodies about not downshifting to 1st at much more than a slow crawl. Normally it will make noise but my guess would be you hurt the bottom sprag in the case. It cost me a bunch of money to learn that lesson myself. I ripped the sprag out of the case, it broke the lugs off the case itself and got itself twisted. The roller bearings blew apart etc. Kinda felt like I was driving with the emergency brake on.Yanno what though it wont make noise because your running full manual. It would only make noise in drive with a standard valve body because the sprag is free spinning. once you go into manual low the sprag locks up. The abrupt lockup is what causes it to break on downshifting. Drop the pan and see if theres any metal laying in there. specifically your looking for rollers that about about 3/8's tall and 1/4 inch across cylinders.
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Old 03-06-2010, 10:00 AM   #5
LongSixEight
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Re: What happened to my trans???

Well Crap. Thats not really what I wanted to hear but, makes sense. I guess another one learned the hard way. I'll probably pull the pan Mon or Tues and check things out. Its the first really nice weekend here and the wife found her honey do list shes been working on all winter. So now I just gotta walk around it in the garage all weekend and ***** and moan about how dumb I am. Thanks
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Old 03-06-2010, 01:24 PM   #6
cableguy0
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Re: What happened to my trans???

Btw as much fun as a full manual valve body is for a street bound truck your better off with a manual/auto. Where you can hold or shift to any gear at any rpm but still have automatic function when in drive. Btw have you looked at the fluid?
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Old 03-06-2010, 06:24 PM   #7
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Re: What happened to my trans???

I went full manual on my truck because I wanted to be able to start in 2nd gear(for burnouts). Can manual/auto valvebodies do that?
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Old 03-06-2010, 11:13 PM   #8
djracer
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Re: What happened to my trans???

Why would you need to start off in 2nd to do a burnout?
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Old 03-07-2010, 12:08 AM   #9
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Re: What happened to my trans???

You never want to start in 2nd gear. You will blow the front sprag out. Starting in 2nd gear puts double the load on the sprag. It doesnt take too many times of doing that before it explodes.
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Old 03-07-2010, 12:19 PM   #10
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Re: What happened to my trans???

Quote:
Originally Posted by djracer View Post
Why would you need to start off in 2nd to do a burnout?
Quote:
Originally Posted by cableguy0 View Post
You never want to start in 2nd gear. You will blow the front sprag out. Starting in 2nd gear puts double the load on the sprag. It doesnt take too many times of doing that before it explodes.
Also if you run a TH 350 don't come out of the water box in second and let it grab traction, also very hard on the sprag.

I put my truck in drive in the water box, flash the converter do my burnout and come out the box in drive. Have never had a problem getting them going, plus the MPH are up on my tires like now, takes less time to heat the tires.
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Old 03-07-2010, 03:13 PM   #11
cableguy0
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Re: What happened to my trans???

You want to start in first and get into high gear to get tire speed up for the burnout but always start in first and gently roll out to ease shock on the drivetrain. never put the transmission in neutral either.
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Old 03-07-2010, 07:45 PM   #12
LongSixEight
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Re: What happened to my trans???

The fluid is as red as red can be and smells fine. What do you mean to never put the trans. in nuetral?
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Old 03-07-2010, 08:09 PM   #13
cableguy0
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Re: What happened to my trans???

If your in process of doing a burnout and you get into a high gear and start to roll out of the box do not go into neutral until the wheels stop moving. get it slowed down and stopped then go into reverse and line up. The fluid wont be cooked from a hard parts failure right off the bat. Having nice red fluid would lead me to believe that you have hard part failure and not cooked clutches. Does reverse work and feel ok? low reverse is the same clutch pack.
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Old 03-07-2010, 09:28 PM   #14
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Re: What happened to my trans???

This is all from YellowBullet.
"If it will light the tires right up in 3rd, then just do it in 3rd. The only reason to do a 2-3 burn-out is if you can't get them spinning easily enough doing a high gear only burn-out". -JP outlaw

"Many a sprag has been broken coming out in 2nd gear. roll through the water in first gear, stop/set your LL and pull into 2nd, wait for the command to start your burnout, get upto rpm desired, pull 3rd so the entire transmission internals are locked together and share the shock when you roll out of the box and tires grab...the only way to do it". -IHI

"It goes for everything, if you can start in high do it. If you can't go for a 2-3 but always leave the burnout in high and try to ease off when the tires start to hook". - Hutch(the trans expert on YB).

"I still have some customers that will not change their style , they go 1-2-3 no matter what I say and they have had good luck and have not damaged anything so far.
I also have several customers that did have major problems , switched styles or burnouts and now have no problems". - Hutch

Most of the experts on that site pretty much say to start the burnout in 2nd and finish in 3rd.
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Old 03-07-2010, 09:39 PM   #15
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Re: What happened to my trans???

1-2-3 burnouts if you let the truck roll and accellerate!! If you stand still, only 1st!! It's only a matter of time before you toast a tranny.
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Old 03-07-2010, 10:32 PM   #16
LongSixEight
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Re: What happened to my trans???

I had to move it out of the shop today. Reverse didnt feel right either but moved it outside. Here in KS we have a good chance of some rain moving in early this week. That means I will probably have time to get it out tomorrow or tuesday. I'll keep you posted, maybe with damage pics. Thanks for all your help.
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Old 03-07-2010, 11:08 PM   #17
djracer
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Re: What happened to my trans???

Is this a th350?
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My Pass Time Show http://s129.photobucket.com/albums/p...Chapter1-0.mp4

So Far my best Times are:

Motor only:
6.44 1/8 @ 104.13
10.39 1/4 @ 125.83

Nitrous Times:
5.785 1/8 @ 118.65 with a 1.336 60ft
9.168 1/4 @ 142.58 with a 250 shot dead out of the hole!
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Old 03-08-2010, 12:43 AM   #18
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Re: What happened to my trans???

Hey man your not far from me. If I can help let me know. Troy
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Old 03-08-2010, 08:55 AM   #19
cableguy0
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Re: What happened to my trans???

I bet you a punch in the gut that if first and reverse and both acting up. You broke the low gear sprag. Pull the pump out and tear it down to the bottom sprag and i bet its mangled and probably spun in the case.
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Old 03-08-2010, 09:19 AM   #20
djracer
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Re: What happened to my trans???

If it is a th350 that is the weak link.
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Special Thanks to All who have helped on the TRUCK!

My Pass Time Show http://s129.photobucket.com/albums/p...Chapter1-0.mp4

So Far my best Times are:

Motor only:
6.44 1/8 @ 104.13
10.39 1/4 @ 125.83

Nitrous Times:
5.785 1/8 @ 118.65 with a 1.336 60ft
9.168 1/4 @ 142.58 with a 250 shot dead out of the hole!
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Old 03-08-2010, 10:54 AM   #21
team39763
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Re: What happened to my trans???

Would it be easy for him to just go buy a hardened sprag and swap it in?
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Old 03-08-2010, 12:06 PM   #22
LongSixEight
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Re: What happened to my trans???

It is a th350. So whats gonna be the best route to take on this one, fix it, junk it, build a new one,gimme some opinions. The engine is a well built 331 probably 400 to 425 hp range built for a 150 to 200 shot. Its in a heavy ole long bed too. I have a glide that I was gonna have built for this but didnt cause these trucks are so heavy.
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Old 03-08-2010, 01:37 PM   #23
cableguy0
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Re: What happened to my trans???

OK theres two sprags in a th350. theres the low reverse roller sprag and the second gear sprag. The sprag that hes likely broken is the lower reverse in the back of the case. The th350 sprag that most people are used to hearing about braking is the 2nd gear sprag. hardened units are readily available for the 2nd gear sprag. You likely wont hurt the low/reverse sprag unless you downshift into 1st at speed. You need to tears your apart to see the extent of the damage. The low/reverse sprag is known to actually spin in the case and rip the lugs out of the case that hold it in place. Teardown is the only way to find out.
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Old 03-15-2010, 05:09 PM   #24
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Re: What happened to my trans???

Are you guys sure that it's bad to start in second?
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Old 03-15-2010, 05:29 PM   #25
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Re: What happened to my trans???

Yes 100% positive. taking off in 2nd puts double the load on the sprag. The sprag will break.
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