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| Synchromesh; pennzoil synchromesh (UPDATE) | |
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| Tweet Topic Started: Sep 21 2012, 07:41 AM (1,573 Views) | |
| 1.0smallblock | Sep 21 2012, 07:41 AM Post #1 |
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DirtBag
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last year i replaced my manual transmission gear oil. my manual specifies GM part# 12346190 75W-90 GL4, but the parts store did not have that. so, i went with valvoline 80w-90 GL-5. today im changing the engine oil and i wanted to change the gear oil too. everyone keeps recommending synchromesh, so yesterday i picked up 3 quarts of pennzoil synchromesh. (they didnt have amsoil synchromesh) and i thought id give that a whirl. the penzoil does say it meets GM requirements, although there is no weight of the oil listed. im not having any transmission issues except 1st and 2nd gear feels a tad "notchy" at times (is that a decent description??) otherwise the transmission shifts and sounds fine. i popped the top and looked at the oil...it looks awfull thin. what do you guys think?? probably cant hurt to try it, but looking for some opinions.
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| idmetro | Sep 21 2012, 07:55 AM Post #2 |
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I've been running it in both my Metros for the last couple of years. One of them had the notchy feel you describe, after adding Syncromesh it has shifted beautifully since. The other car had 1st and 2nd gear syncro issues, 2nd gear issues have been reduced allowing me to delay having to swap it until I'm ready. It looks thin but works well! |
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| j63812f | Sep 21 2012, 08:01 AM Post #3 |
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J R
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I put std ATF into one of my units and it corrected a 'notchy' first gear......i really did have difficulty getting it into 1st until I put this stuff in. I tried it on my 96 that has a bad entry from 2-3 but it didnt help that one. |
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| starscream5000 | Sep 21 2012, 08:24 AM Post #4 |
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Got 70 MPG?
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Synchromesh is supposed to be a thinner weight oil. It allows the synchros to spin up and slow down faster for your gear changes. It's still formulated for manual transmission use, so you'll be fine with it
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| 1.0smallblock | Sep 21 2012, 08:29 AM Post #5 |
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DirtBag
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great explaination, thanks.
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| j63812f | Sep 23 2012, 08:22 AM Post #6 |
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J R
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Chris you rock
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| 1.0smallblock | Sep 23 2012, 09:21 AM Post #7 |
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DirtBag
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ok, the other day i replaced my manual transmission fluid with Penzoil Synchromesh. the results arent "jaw dropping" but i noticed it feels smoother and shifts a little easier. that "notchy" feeling seems to have diminished quite a bit, although it wasnt bad to begin with. well see how this goes, so far i like the results.
Edited by 1.0smallblock, Sep 23 2012, 09:53 AM.
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| j63812f | Sep 23 2012, 12:37 PM Post #8 |
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J R
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Thats exactly what that ATF did for me, it def smooothed things out. It did correct the notchy entrance to 1st so Im leaving it in. I dont know if the 7.99 synchromesh would have done me any better than the 4.49 ATF.
Edited by j63812f, Sep 24 2012, 07:35 AM.
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| Woodie | Sep 24 2012, 04:57 AM Post #9 |
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http://tinyurl.com/Synchromesh-price
Edited by Woodie, Sep 24 2012, 04:58 AM.
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| j63812f | Sep 24 2012, 07:36 AM Post #10 |
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J R
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edited accordingly.
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| j63812f | Sep 24 2012, 09:46 AM Post #11 |
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J R
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Chris, if you ever get the chance to take one of these apart, do it, its VERY enlightening... I always wondered what was going on in there and how the synchros work. Now it seems easy, but then again the one I rebuilt was in good mech condition. The synchro spins as part of the the selector and brings the gear up or down to speed to match on the approach. Its really awesome, I know its common stuff but the engineering is impressive to me. Edited by j63812f, Sep 24 2012, 10:24 AM.
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| 3tech | Sep 24 2012, 10:28 AM Post #12 |
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Synchro, ATF or 5W30/10W30 motor oil, I don't think it makes much difference. Either will do the job. |
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| rjsdotorg | Sep 24 2012, 11:06 AM Post #13 |
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R E Member
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I have a question on all these fluids (I bought Pennzoil synchromesh): are the seals in the trans designed to resist all the additives they put in ATF etc? I know that ATF will swell/destroy a number of types of rubber products and seals not designed for it. I made the mistake of lubing some urethane bushings with it once; they swelled and stuck in a few days and I had to cut them out. OTOH I suspect that many of the "leak stop/seal repair" products are the same additives. |
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| j63812f | Sep 24 2012, 12:23 PM Post #14 |
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J R
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Im no expert, but trans fluid is designed to protect the seals of the trans, inner and outer(axles) but frame and suspension bushings will def absorb it and swell, probably should have used a silicone lube on your bushings. |
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great explaination, thanks.
3:34 AM Jul 11