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  1. #1
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    Exclamation Won't shift from 30mph to 47mph, no matter what i do! HELP!

    There's nothing like rapping out in 2nd gear because the speed limit is 40 and your car won't shift! I did the tranny fluid, new filter, synthetic fluid etc and I can't really say if it was happening before that or after because she has had soooooooo many things go wrong I lost track in the process of fixing them all. I would really like to know why it's doing this because it's not showing any codes when I run them with my million dollar snap on scanner, so wtf! I'm pretty sure it's not good for it and would like to avoid any other problems as a result of this one. A lot of people who I have asked said it was the tranny slipping, then I took them for a ride and when it's stuck between those speeds I press on the gas and she jumps to it instead of slipping like assume the people thought it would, and I'm still at a loss as to why and now, so are they. Help me! And if anyone knows what other cars have these same tranny's (if any) and have some insight on a good avenue to take if and when I decide to replace it that would be soooooo awesome!

  2. #2
    Turbo is the way to go. Fivefingerdeathpunch's Avatar
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    Default Re: Won't shift from 30mph to 47mph, no matter what i do! HELP!

    So it's stuck in first gear or skipping second gera and going straight to 3rd?

    Can you command each gear with the scanner?


    You didn't say if this was a NA car or a S/C car.

    Grand prix, regals, park ave, bonnevilles all run the same S/C transmission. Grand prix, regals, monte carlo, impala's all run the same NA transmission. Just be aware that some impala's, most it not all bonnevilles and some others run a different gear ratio than grand prix's and regals. Some can be 2.86 and 3.05 where as the regal/grand prix are 3.29.

    SMGPFC Member #1

  3. #3
    GT Level Member mguzzo's Avatar
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    Default Re: Won't shift from 30mph to 47mph, no matter what i do! HELP!

    i don't understand what problem you are describing. Are you saying that between 30 and 47 mph, you don't get a downshift when you step on the gas? Or you don't get any upshift out of second gear between those speeds?
    --
    Current '98 GTP Coupe: Still stock and rust free. That will change.
    Old '98 GTP Coupe: VS Cam, 3.0, S2IC, 42.5#, TOGs, N*/LQ4, Corsa. it once ran a 13 flat
    Older '98 GTP Sedan: Pullied, rockered, SSIC, etc. Stock 14.33 @ 96.5 / PB: 13.89 @ 101

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    Default Re: Won't shift from 30mph to 47mph, no matter what i do! HELP!

    It won't up shift between those speeds, I"m pretty sure it only goes through the first gear and the second is the one that has the problem. Sometimes she's responsive and sometimes she's not I just got a gauge to test the transmission in hopes of narrowing down the issue, have you ever done that before? I know I'm not supposed to run the test for longer than 2 minutes and the car has to be at running temperature, anything else I need to know or can do???

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    Default Re: Won't shift from 30mph to 47mph, no matter what i do! HELP!

    the car is supercharged and the only reason I haven't set it on fire at this point actually haha so what I meant was it wont go from 2nd to 3rd from what I can tell, I only feel it go through first gear before it starts this crap so I assume 2nd to 3rd is correct. and i am pretty sure I can command the gears from my scan tool, it's the snap on modis if that helps at all. I did a test on someone elses transmission a while back with it but I am not sure if it was the gears I was commanding or something else, all I know is I started the test and went up from 1, every five seconds until I got to 10, recording the reading on the gauge each time. I have been wanting to do this to my car but i'm just really uncomfortable with what I've been told about that particular test and what it can do to a transmission if something went wrong. is there any steps I could and should take that you think would be helpful??

  6. #6
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    Default Re: Won't shift from 30mph to 47mph, no matter what i do! HELP!

    First off.. did you drive the car previous to all the work and verify it had all four gears working?

    When you did the trans.. I assume you checked the level with the engine running? If not.. that's likely the issue
    Use the modis to command shifts, I'm pretty sure it'll do it.

  7. #7
    Transmission Expert Trannyman95's Avatar
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    Default Re: Won't shift from 30mph to 47mph, no matter what i do! HELP!

    If 3rd clutches or sprag are bad it will act like this and will seem stuck in 2nd until the 3-4 shift.

    Under light throttle it will shift 1-2 around 13 mph, 2-3 shift about 25 mph, and 3-4 shift at 44 mph. This is based off of a 99 file and will vary a bit depending on throttle position but is your average shift speed ranges.

    With your SnapOn Modis you just need to get into the Transmission data menu and watch "Gear" or "Current Gear" and it will show 1-2-3-4 based on what the pcm commands. Odds are around 25mph you will see 3rd gear commanded but no rpm change. You can also watch "Gear Ratio" and it should read 1.00 in 3rd gear. If it is still showing around 1.6 ratio after the 3rd is commanded that is saying the computer is doing its job. Since you have 1st, 2nd, and 4th that is proving both shift solenoids work.

    Another crude test you can do is unplug the main transmission case connector under the throttle body area. It is a round 20 way connector. Squeeze the sides and pull it back. There is no electrical control at this point and gives limited operation. You will have max line pressure, Reverse, 3rd gear in D and 3 ranges, and 2nd gear in 2 and 1 ranges. You may have 3rd when doing this due to the max line pressure but if you take off in 1st or 2nd range (will be in 2nd) and upshift to 3rd and still no change then it is definitely internal and proves a 3rd clutch or sprag problem. Not uncommon on the 97-02 models, sorry I didn't see mention of the year of your car. Hope this helps

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    Default Re: Won't shift from 30mph to 47mph, no matter what i do! HELP!

    Thank you very much for you response, very very helpful. I guess I didn't state the year of my car ha oops...! It's a 97 so that works with what you were explaining. The last paragraph where you explain a test to see whether the problem is internal and 3rd clutch or sprag etc. sounds like exactly what I need but I don't completely understand what I do after I unplug the connector. I am very familiar with these cars and am capable of doing this test I just won't feel comfortable doing anything unless I am confident I fully understand what I need to do. If you wouldn't mind going into more detail for me on the procedure/steps you would be my hero!!! Thank you again!

  9. #9
    Killa Bee Scottydoggs's Avatar
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    Default Re: Won't shift from 30mph to 47mph, no matter what i do! HELP!

    you have lost 3 rd gear. same thing happened to mine. 2 nd gear screaming to 45 mph, where it shifts into overdrive.

    98 Buick Regal GS, F body brakes, Caddy STS wheels, tinted tails L36 bottom end, lightly ported heads, 1.95 roller rockers, headers, 2.8, FSIC, 42 lb injectors, a BrandonHall rebuilt trans, DHP tuned and AEM water/Meth injection https://goo.gl/gpV5kW

  10. #10
    Donating Users 16MustangVet's Avatar
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    Default Re: Won't shift from 30mph to 47mph, no matter what i do! HELP!

    You can see if the shift bands are broken by taking the filter out and looking at the valvebody to see where the lugs are on the shift bands.

    I dont remember which ones or if all of them are exposed.

    Been a while since i looked through a 4t65 ATSG manual.
    How I treat my car: wreck,fix, repeat.

  11. #11
    Killa Bee Scottydoggs's Avatar
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    Default Re: Won't shift from 30mph to 47mph, no matter what i do! HELP!

    this aint no band smart guy, its the 3 gear sprag went and took a dump on him.

    thanks for stopping by tho........

    98 Buick Regal GS, F body brakes, Caddy STS wheels, tinted tails L36 bottom end, lightly ported heads, 1.95 roller rockers, headers, 2.8, FSIC, 42 lb injectors, a BrandonHall rebuilt trans, DHP tuned and AEM water/Meth injection https://goo.gl/gpV5kW

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    Default Re: Won't shift from 30mph to 47mph, no matter what i do! HELP!

    Well hell, what now? What would you suggest as the best plan of action??? Preferably the most inexpensive yet efficient avenue but if there isn't one then lay em on me, at this point it really doesn't matter about the money I guess cuz my sanity is on the line lol

  13. #13
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    Default Re: Won't shift from 30mph to 47mph, no matter what i do! HELP!

    Do what trannyman stated.

    Pull connector off trans. Start car and put car in 2 on shifter start driving, when you get moving put the shifter in 3 or D. If you feel no difference, the problem is the sprag or clutches for 3rd gear.

  14. #14
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    Default Re: Won't shift from 30mph to 47mph, no matter what i do! HELP!

    AMAZING! I'll do that today and post what happens later...

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    Default Re: Won't shift from 30mph to 47mph, no matter what i do! HELP!

    Ok so just an update, I hooked up my Snap-On Modis and went to the Command Gear section where it takes over the transmission basically and I just hit the ' Y ' button to shift. The one problem I found was, like someone previously said in this thread, I do not have 3rd gear, it's going straight from 2nd to OD explaining why it won't shift until 47MPH! AMAZING! When I tried to command it to go into the 3rd from 2nd the RPM does not change period when they definitely should drop and start 3rd gear but it doesn't, so thank you to the two or 3 that mentioned this particular solution.

  16. #16
    Killa Bee Scottydoggs's Avatar
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    Default Re: Won't shift from 30mph to 47mph, no matter what i do! HELP!

    i was in the same boat, my first blown tranny, oh memorys....lol

    you might have noticed before you lost 3 rd gear some rpm surging around 30-35 mph light on the gas in 3 rd, what mine was doing for a month or so, then one day 3 rd gear was just no more.

    98 Buick Regal GS, F body brakes, Caddy STS wheels, tinted tails L36 bottom end, lightly ported heads, 1.95 roller rockers, headers, 2.8, FSIC, 42 lb injectors, a BrandonHall rebuilt trans, DHP tuned and AEM water/Meth injection https://goo.gl/gpV5kW

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