Can synthetics help automatics?

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175
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CA
I've heard claims that for smaller automatic cars where the shifting is a bit jerky, a synthetic oil can help smooth it out. Is this likely? If so, why? Thanks
 
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7,430
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beaver land EH?
IMHO nope. Syn plays the role of being a bit more robust and can take more heat. In ATF fluid application, it still bears the same viscosity and with the same friction of coefficient for the type of transmissions calling for, thus even with the lowly conventional oil base, syn still shifts the same. Q.
 

mozart

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175
Location
CA
 Originally Posted By: mozart
I've heard claims that for smaller automatic cars where the shifting is a bit jerky, a synthetic oil can help smooth it out. Is this likely? If so, why? Thanks
I need to clarify that I'm referring to the engine and not transmission oil/fluid. Thanks
 
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7,430
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beaver land EH?
IMHO in engine, syn is good for the following: (a) resists thermal breakdown better (b) low temperature flow The performance gap has narrowed significantly over the past 2 decades or so to the point where nowadays, conventional oils that passed ILSAC GF-4 or similar already comes neck and toe to those "so-called" syn in the engine lubricant performance. So, unless you have a seriously stroked engine that the sump cannot take on the extra heat produced by your engine, or you run your engine in -40C below all the time, otherwise, I personally do not see the true need to run syn (*or according to Mobil1/Castrol Syntec, they interpretation of "synthetic" in NA*). Q. p.s. if your car feels jerky, look into the engine's ignition or fuel problems first. Inferior fuel and/or poor ignition will cause that too.
 
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1,093
Location
Kentucky
 Originally Posted By: mozart
I've heard claims that for smaller automatic cars where the shifting is a bit jerky, a synthetic oil can help smooth it out. Is this likely? If so, why? Thanks
You are asking about synthetic transmission fluid, not synthetic engine oil aren't you? I have used synthetic transmission fluids since about 1988+/-. I change the factory fill transmission fluid and filter very early(1000-5000 miles), and fill with synthetic transmission fluid. I then change the fluid and filter on a regular schedule. I never had an automatic transmission problem but the highest mileage I have ever put on an automatic is now right at 210,000 miles.
 
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645
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US/UK
 Originally Posted By: mozart
I've heard claims that for smaller automatic cars where the shifting is a bit jerky, a synthetic oil can help smooth it out. Is this likely? If so, why? Thanks
No. Synthetic oil will have no effect on transmission shifting parameters. However, when you decide to replace your current transmission fluid I would highly recommend synthetic in combination with synthetic engine oil. The synergy of this combination is amazing.
 
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14,013
Location
Retired | Wausau, WI
 Originally Posted By: mozart
 Originally Posted By: mozart
I've heard claims that for smaller automatic cars where the shifting is a bit jerky, a synthetic oil can help smooth it out. Is this likely? If so, why? Thanks
I need to clarify that I'm referring to the engine and not transmission oil/fluid. Thanks
Your choice of engine oil will have nothing to do with how your automatic transmission shifts.
 
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1,093
Location
Kentucky
 Originally Posted By: mozart
 Originally Posted By: mozart
I've heard claims that for smaller automatic cars where the shifting is a bit jerky, a synthetic oil can help smooth it out. Is this likely? If so, why? Thanks
I need to clarify that I'm referring to the engine and not transmission oil/fluid. Thanks
WHOOPS....This came up after my post. Guess I type a little slow.
 
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3,130
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Phila,PA
 Originally Posted By: Johnny
 Originally Posted By: mozart
 Originally Posted By: mozart
I've heard claims that for smaller automatic cars where the shifting is a bit jerky, a synthetic oil can help smooth it out. Is this likely? If so, why? Thanks
I need to clarify that I'm referring to the engine and not transmission oil/fluid. Thanks
Your choice of engine oil will have nothing to do with how your automatic transmission shifts.
+1 If your tranny is acting up, take it in for a fluid and filter change. If it still acts up take it to a good Trans shop.
 
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158
Location
PA
Over the years of switching everything to synthetics, the only place that I really noticed any major change was when I change the tranny fluid. My 04 Astro within 50 miles just seemed to be so much smoother, just felt completely different. Ditto on other vehicles I owned.
 
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22,679
Location
Dallas,Tx USA
Only place I`ve ever felt a real world difference with synths was in the manual tranny. Dinos run day/night smoother in every engine I`ve ever owned. You`d think if it was placebo efect,an expensive synth would "feel" better,but the cheap dino wins the prize imo.
 
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25,046
Location
ON, Canada eh?
I switched to a synthetic ATF fluid and it made my transmission shift like a hot knife through butter. It also seems to go into overdrive at a lot quicker when the engine is cold. IMO it can have an effect on shifting performance.
 
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434
Location
MD
Wait a second guys. If you are running a 30 or 40 weight oil and you go to a 20 weight, there is going to be less drag on the engine. You may hit rpm shifting points quicker.
 
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343
Location
Grand Caymans
RPM shift points shift at the set RPM. That doesn't change. When you hit a certain RPM the transmission shifts. If you press the pedal harder you get to pre-set shift points quicker but it is still shifting at the exact same RPM. This thread is confusing as heck! Is he asking about syn trannie fluid or what?
 
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14,778
Location
Illinois
Over the years I have put M1 ATF in several trannys and I can say I have noticed smoother up shifting and down shifting.
 
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25,046
Location
ON, Canada eh?
 Originally Posted By: GrampsintheSand
RPM shift points shift at the set RPM. That doesn't change. When you hit a certain RPM the transmission shifts. If you press the pedal harder you get to pre-set shift points quicker but it is still shifting at the exact same RPM. This thread is confusing as heck! Is he asking about syn trannie fluid or what?
This may be true in older transmissions that were all mechanical in nature and relied on springs and oil pressure to create the shift point, but in newer transmissions that use electronic solenoids and other fancy electronics the shift points change based on the drivers foot pressure, input/output shaft speeds, software, fuel trim %, vehicle load, fluid temperature, fluid pressures. This is to balance performance, fuel economy, heat generation and component wearing. ;\)
 
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343
Location
Grand Caymans
Stevie...I use HP Tuners and do all the programming on all the Pro Stock 4L's in the shop. What you meant to say is the TPS reads throttle position and adjust based on set parameters you have programmed. But the programs do not change. Air Fuel trims have nothing to do with shift points or shift firmness.
 
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25,046
Location
ON, Canada eh?
With my pro scan tool hooked up monitoring the systems in Chrysler and my Hyundai vehicle you can see the shift points changing based on all this data. It depends on the design of the transmission and the control module, some are simple and some are more complex. I don't know about the transmissions you have done, but I can assure you these are different.
 
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1,776
Location
Kingston
I switched to synthetic fluid in both of my 2004R GM auto overdrive transmissions a while back. Both had no real noticeable effect to me on the shift quality. Both had already held up a long time on conventional fluid, but I've got over 170k on one and over 200k on the other one which has been driven hard for about 7+ years now and pulled a trailer by the previous owner. IMO for the price of it, it's worth the investment in synthetic just cause my cars are already old and a lot of wear on them, I want the trans to hold up a long time. My new winter beater had 304k miles on the original 2004R trans when it failed because the previous owner let it run low on fluid for a week and kept driving. AFAIK it never had synthetic fluid and the last change interval was probably much longer than it should have been.
 
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1,776
Location
Kingston
oh and btw, IMO an improvement in shift quality is a firmer quicker shift. This means less clutch wear and longer life. If I can afford it this year, one or both of my 2004R's will be getting shift kits to improve the shift quality and make them last longer. USUALLY, a smooth shift means less service life out of your transmission. So you better enjoy that smooth feeling shift cause your going to pay for it. lol. My 304K mile Caprice had the smoothest shifts ever right before the trans finally packed it in. The low fluid was the biggest issue, but I'm sure it was already getting pretty worn. Also my friends AOD in his 89 Crown Vic had very very smooth unnoticeable shifts right before it lost 3rd and 4th gear and started shuddering like crazy. The fluid also went black in a very short period. My experience goes further than this, but just wanted to give you guys some examples.
 
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