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grinding when upshift into 4th

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Old Jun 4, 2018 | 04:43 PM
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St. Jude Donor '05-'06-'07-'08-'09-'10
Default grinding when upshift into 4th

Since I got the car back from getting a new rear diff installed. The car now grinds going into 4th. But only on the upshift 3-4 shift, if I downshift from 5 -4 I can shift easily and smoothly.

I have already re-aligned the shifter to make sure that wasnt the problem. And that didnt change anything.

They changed the fluid when they did the diff install and put in stock dex-3. I have redline d4 in my garage and going to change the fluid back out to see if that helps.

But do you guys have any other ideas about this? The grinding only going one way has me really confused
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Old Jun 4, 2018 | 06:08 PM
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maybe the 3-4 synchro... the teeth on the gear that mesh with the synchro can also get worn out and that will lead to having to replace the whole gear
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Old Jun 4, 2018 | 06:43 PM
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I was having a grinding issue with some gears and thought I needed a new trans.
Took it to a shop that drained the fluid and put Amsoil ATF in it and now all my gears shift like they should. My popping out of gear is completely gone. This stuff is magic!!!
$80 and all my problems are gone.
The shop may have used the wrong fluid or not enough.
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Old Jun 4, 2018 | 08:50 PM
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St. Jude Donor '05-'06-'07-'08-'09-'10
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I’m hoping it’s the fluid. But since it’s just one gear I’m afraid the guy who did the diff messed something up. But I can’t prove that.
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Old Jun 4, 2018 | 08:57 PM
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I don't know how they could have messed up anything internally, the trans doesn't even have to be removed to swap the diff out... hopefully the redline fluid will help
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Old Jun 4, 2018 | 09:14 PM
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I know he changed the fluid in the tranny for some reason when I didn’t ask him. Which makes me think he dropped the tranny also
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Old Jun 4, 2018 | 09:19 PM
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even if he pulled the trans you still don't have to drain the fluid in it, it won't leak out unless you flip it over
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Old Jun 4, 2018 | 10:07 PM
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St. Jude Donor '05-'06-'07-'08-'09-'10
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Gotcha. Hopefully it’s just fluid. I’m off Friday so should be able to do the change then just as a why not.

Dont have much faith that’s the problem. But if it winds up to be that, it’s worth the try
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Old Jun 4, 2018 | 10:10 PM
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hopefully it helps... I wasn't trying to discourage you or anything, it just makes me wonder what they did or didn't do
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Old Jun 4, 2018 | 10:40 PM
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St. Jude Donor '05-'06-'07-'08-'09-'10
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Not discouraged. Just annoyed with the hole thing.

His price doubked for the install and he didn’t tell me until pickup and now this. Like I said earlier I can’t prove anything he did or didn’t do to this. So I’m stuck with the repair
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Old Jun 5, 2018 | 09:36 AM
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St. Jude Donor '05-'06-'07-'08-'09-'10
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So I was playing around in the car this morning.

And so I decided to try something. So going from 3-4 where the grind is. If I kind of move the stick. Back and forth while going into 4th I can get there with no grind. But if I try pulling it straight back there is still the grind. So I have to think something is not lined up correctly in there.

Last edited by MBVette; Jun 5, 2018 at 09:37 AM.
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Old Jun 9, 2018 | 08:09 PM
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St. Jude Donor '05-'06-'07-'08-'09-'10
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Changed the fluid out and as expected no big change.

I can can actually get it j to 4th w/o grinding if I shift really lowly. Like the rpms are coming down and then I shift. If I try to shift while accelerating it grinds badly.

Looks like ill I’ll be skipping the 3-4 shift for awhile.
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