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Old 03-18-2015, 08:55 PM   #1
theuglyduckling
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th350 modulator

ive got a th350 in my 76 stepside that is leaking tranny fluid im pretty sure through my modulator. im getting tranny fluid in my vacum line between the carb and modulator. Im pretty sure my modulator has about gone out. leaks fluid crazy fast. enough that its difficult for it to get to go and stay in drive, slips out at stop lights. usually stops after thoroughly warmed up. big question is the difference between color coded modulators. recommendations?
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Old 03-19-2015, 03:59 AM   #2
donut
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Re: th350 modulator

Red stripe, it's adjustable. Odds are your local auto parts store will give you this one anyway.
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Old 03-19-2015, 12:17 PM   #3
SkinnyG
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Re: th350 modulator

I have a green stripe, which is also adjustable. I cannot find what the differences are.
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Old 03-19-2015, 12:24 PM   #4
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Re: th350 modulator

With a skinny blade screwdriver, you can adjust the shift points slightly (through the vacuum side of the modulator). I've never seen an adjustable green, most are red-stripe as mentioned previously.
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Old 03-19-2015, 02:46 PM   #5
theuglyduckling
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Re: th350 modulator

much appreciated. i called around and found a red stripe adjustable for 14 bucks and in stock compared to 30 bucks and a couple days wait haha. i'd mark that a win. i'll put it in this evening and hopefully that will take care of my shif issues and really bad trans fluid loss
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Old 03-19-2015, 03:39 PM   #6
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Re: th350 modulator

red stripe green stripe? ive never heard the term before what does it mean?
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Old 03-19-2015, 05:47 PM   #7
donut
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Re: th350 modulator

It's actually a paint stripe around the vacuum can on the modulator. I believe factory was black stripe, non-adjustable. The red (green?) are adjustable. This way you can fine tune your shift points.

I did see on O'Reillys sight, the adjustable green stripe.
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Old 03-19-2015, 09:11 PM   #8
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Re: th350 modulator

I always heard the "red stripe" was the one to get. I needed one, and the green stripe was in stock. I just cranked the screw inside one turn the other day. Mine ~is~ adjustable. Makes no sense.
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Old 03-20-2015, 08:47 PM   #9
theuglyduckling
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Re: th350 modulator

I picked up a red one and it's adjustable. Still having issues with it coming out of drive after first driving but goes away once warmed up. Much better though. Haven't adjusted it yet, but I'll fine tune it over the weekend
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Old 03-20-2015, 08:58 PM   #10
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Re: th350 modulator

Does it physically shift out of drive, or does it just lose forward motion?

If it shifts out, I'd look at the shifter itself, not the trans.
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