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| 0-40w Euro Mobile Synthetic too thin for tranny? | |
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| Tweet Topic Started: Jan 18 2014, 11:53 AM (579 Views) | |
| heckling7 | Jan 18 2014, 11:53 AM Post #1 |
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Being Synchromesh is about $9 a bottle, I was wondering if the GL-4, 0-40w Euro Mobile Synthetic I put in the engine would work in the transmission as well? Its under $25 a 5 quart jug at Walmart. I'm near 40k on my latest change of Synchromesh and due for a change this spring. Would the 0-40 be too thin for a manual transmisson? Synchromesh doesn't seem much thicker and I understand its not synthetic anyway. If 0-40 Euro is not ideal then what synthetic motor oil weight would you suggest for a transmission? I saw a 15w-50 Mobile Syn. at Napa. Would GL-4 specs be better than GL-5 for a transmission or no matter? Otherwise if motor oil is a no-go I was thinking of just getting 2 bottles of Synchromesh and fill the rest with 0-40w Would mixing harm?If synthetic motor oil is good to go I figure I could cut the cost in half from the typical $27 bill for 3 bottles of Synchromesh. BTW, what is in Synchromesh that makes it better than a comparable weight synthetic motor oil, if any? Thanks
Edited by heckling7, Jan 18 2014, 01:53 PM.
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| truckjohn | Jan 18 2014, 12:52 PM Post #2 |
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Why? I mean... Come on - really... Why? How much hassle and expense is it going to be to do Bearings and Brass on your manual tranny? How much do you honestly drive a year? Most people - 40K would be 2 or 3 years worth... So... if you use Motor oil vs Synchromesh.... You would save $3.00/qt.... so $9.00 over 3 years? Come on - That's like brown bagging lunch TWICE in 3 years! Synchromesh is the stuff you want. GL-5 would only be my choice if I could absolutely NOT find Synchromesh... DO NOT USE GL-4... It is made for axle gears - and will tear up your synchros... Thanks |
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| 3tech | Jan 18 2014, 01:45 PM Post #3 |
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It will be fine. The FSM used to spec 5W30 for the manual trans. for cool weather. I've used motor oil and ATF many times. Synthetic ATF might be even better. I believe Synchromesh is GL4, and ATF should be too. |
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| truckjohn | Jan 18 2014, 03:13 PM Post #4 |
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Here's one more thing... Remember that the additive packages in Motor oil are made so that when you BURN them - they don't clog up a Catalytic convertor.... They are also made to deal with combustion byproducts that cause corrosive compounds and ash..... They also gotta cooperate with sliding bearings and cold starts... don't want to starve your engine bearings on a cold start, do you? You don't have much of that issue in Transmissions.... You won't get much Combustion gas... so cross that one off the list... and you aren't constrained by additives creating ash that would clog up a Cat.... So... The additive packages can be much more aggressive and more suited towards the sort of conditions you would see inside a Transmission..... Thanks |
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| GeoChris | Jan 20 2014, 09:54 PM Post #5 |
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New Member
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"the additive packages in Motor oil are made so that when you BURN them - they don't clog up a Catalytic convertor...." Since when? I never heard that one!? They have taken out phosphor and zinc to try to eliminate that, but, that wears your engine down faster, so, its kind of reverse. |
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| perfesser | Jan 20 2014, 11:22 PM Post #6 |
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Elite Member - Former Metro owner
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Either way, engine oils are custom designed for the operating environment inside an engine, and transmission oils are custom designed for the operating environment inside a transmission. I had an old Mercedes 240D once that used ATF in the manual tranny and the rear end, but they were designed for it. Our Geo transmissions are not designed for engine oil use. Anecdotal "evidence" (I knew a guy once who ...) about a case where someone "got away" with it is as convincing as talking about your great-uncle who smoked 2 packs a day, never had a sick day in his life and was in perfect health when he fell down that mine shaft ... Exceptions are a poor standard to use when making expensive decisions, like your transmission or lung cancer!
Edited by perfesser, Jan 20 2014, 11:24 PM.
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