Sub Standard Upshift Diagnosis

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Old September 26th, 2013 | 11:24 AM
  #41  
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It's a slotted screw adjustment. Do not turn in too far as it has no stop and will end up in the housing, don't ask me how I know. When you go to change the unit, jacking the car up from the passenger side only will shift the fluid to the drivers side of the trans and your puddle under the car will be minimal.
Old October 2nd, 2013 | 08:14 PM
  #42  
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Was feeling great this morning, got my new modulator in the mail.

Go to remove the old modulator....

SNAP

Screw sheared right off.. Now i'm not sure what to do, a steel screw stuck in an aluminum case.. Do i need to remove the crossmember to get a drill in there and drill it out? There's almost no room in there..
Old October 2nd, 2013 | 08:27 PM
  #43  
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Aw, jeez.

Yeah, I've never had to do that one before, but I would say that removing the crossmember, the shifter linkage, and the fan shroud, and allowing the transmission to hang downward as much as possible in the back would probably give you the best access.

Centerpunch very carefully, and as deeply as possible, then drill with progressively larger bits.
There's a good chance that heat from drilling might loosen the stub, so use a good quality easy-out every now and then to see if it will budge.
If worse comes to worst, drill it right to the threads and try to re-tap it.
If that doesn't work, drill it farther and Helicoil it, or just tap it oversize.

On the good side, it's not a precision-located hole - as long as it holds the modulator down, you're good to go.

- Eric
Old October 2nd, 2013 | 08:32 PM
  #44  
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It's a long shot but try this. Grab a center punch and give the center of the stub a good whacking. Then Grab a flat screwdriver and with one of the pointed ends try to tap it in a left turning direction with a hammer on the outside of the stub diameter. This worked for me when I broke the pin that held the pin on the spider gears on a differential.
Old October 3rd, 2013 | 05:33 AM
  #45  
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You could try slotting the screw w a Dremel and than backing it out w a flathead screwdriver, even if its flush w the case the Dremel will easily cut the alum and if your careful and the screw comes out it will allow you to just screw the new one in
Old October 3rd, 2013 | 06:46 AM
  #46  
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So it basically broke about 1/16 of the way into the little ear that the screw is held into...

I've never used helicoil... I'm hoping that i can get it out and re-tap.

Should i be worried that lowering my transmission that much will damage my engine mounts? I just put new ones in last week.
Old October 3rd, 2013 | 07:05 AM
  #47  
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Also, do you guys have tips on removing totally seized crossmember bolts?

One of the 4 just broke off, the other two turn, but i can't get a boxed wrench on the top end to loosen it up.
Old October 3rd, 2013 | 07:29 AM
  #48  
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Originally Posted by Tony72Cutlass'S'
Also, do you guys have tips on removing totally seized crossmember bolts?

One of the 4 just broke off, the other two turn, but i can't get a boxed wrench on the top end to loosen it up.
That's where a whizzer is your friend. Worth the $60-80.

- Eric
Old October 3rd, 2013 | 07:30 AM
  #49  
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Originally Posted by MDchanic
That's where a whizzer is your friend. Worth the $60-80.

- Eric
I have an angle grinder.. but it seems the bolts are a little bit recessed.
Old October 3rd, 2013 | 06:26 PM
  #50  
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This is a common issue with a TH350 trans, especially one that doesn't leak! If the trans doesn't leak, you gotta deal with the "environmental Loctite". You can get a repair clip from TransStar that uses a oil pan bolt to hold the modulator in. Go to your nearest trans shop and look through the catalog. Its not very expensive, and much easier than trying to remove a broken bolt from the case
Old October 3rd, 2013 | 06:34 PM
  #51  
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Originally Posted by matt69olds
You can get a repair clip from TransStar that uses a oil pan bolt to hold the modulator in.
Now THAT is useful information!

- Eric
Old October 4th, 2013 | 12:36 AM
  #52  
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Gentlemen,

I managed to McGyver a solution this evening using an old Idle stop solenoid bracket. Except now... my transmission won't shift out of 1st gear unless i give her full throttle... Is it possible i installed this incorrectly?? i just slipped it in and connected the vaccum hose.

Could my vaccum line be broken...

WOW, i had no idea that trans-star makes one of those...

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Last edited by Tony72Cutlass'S'; October 4th, 2013 at 06:41 AM.
Old October 4th, 2013 | 06:53 AM
  #53  
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So i'm Completely stumped, i checked all the lines yesterday, they seem to be on there pretty good. I'm thinking maybe the steel line is broken somewhere...

Obviously, if i had my foot buried in the gas, the modulator would tell the transmission to shift hard and long. Which is exactly the way it's acting. So i'm thinking...

1) The modulator was installed incorrectly
2) The Line is busted somewhere
3) This fram modulator is Cr@p
Old October 4th, 2013 | 05:46 PM
  #54  
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If it shift the way you expect at WOT but not at part throttle you have a problem with the detent cable or modulator.

Do you have a good vacuum signal at the modulator? No vacuum=late hard upshifts. Are you POSITIVE the detent cable moves freely in the cable casing? From inside the car you should be able to pull the detent cable at the gas pedal and have it retract quickly into the casing. If not, the detent system is activated. Detent system=late hard upshift.

I like the Macgyvered modulator bracket! Looks very similar to the part from transtar. Is the modulator bottomed out in the bore? Have you tried turning the adjustment screw out a few turns? The modulator screw will change shift points a few mph either way.

I think its time to drop the pan and make sure the detent system works correctly. If your worried about making a mess order a drain plug kit, them drill a hole in the pan (where you want the plug) while its installed. Let it drain overnight. Once as much of the oil has drained its much easier to remove the pan without taking a ATF bath.

When the pan is off you can see the detent lever, make sure it moves freely, and moves with the throttle. Make sure it returns freely to its idle position.
Old October 4th, 2013 | 07:45 PM
  #55  
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Now I'm not saying this should be done but I have reused new trans fluid when I had to re do the pan gasket on my th400 I did the drainplug drill deal as matt69olds suggested but. I got some paint filters from work doubled em up in to a funnel then it filtered as it went into a clean catch pan. Save me 30 bucks influid and no metal fragments went in. I also filtered it when I put it into the quart bottles with new filters. Saved me some money lol.
Old October 4th, 2013 | 09:57 PM
  #56  
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Gentleman,

The old steel modulator line was broken!

I replaced it temporarily with a full 5' length of tubing...

AND MY CAR SHIFTS LIKE A DREAM NOW.

At part throttle, you can't even tell it's shifting.

At Full throttle,the tires chirp. It's the perfect beautiful delicate balance between power and finesse.

Thanks all for your help and encouragement!
Old October 5th, 2013 | 03:39 AM
  #57  
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You're welcome, Tony. Glad you figured it out, and glad it was something simple, cheap, and easy.

- Eric
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