fortheluckyones

^^^THANK YOU SIR^^^....point proven. the 4l60e tranny's are designed to slip between shifts, since synthetic is slicker than dexIII, it could cause premature wear. if your running a modified 4l60e or a TH-400 or anything like that, i would recommend nothing less than synthetic just for the peace of mind. yes, it is more expensive but worth it in the long run.

Rebelord

iTrader: (2)

I like some synthectic stuff. But when I bought my Yank stall. I was told specifically to run normal Dexron and NON synthetic. So, thats what I'm doing to keep warranty. I have run the Royal Purple sythetic before and litterly 2weeks 300mile my tranny went to ****, thats from a fresh rebuild. So after that I stopped using it and just run Napa Premium Dexron 3.

Ski

Black99CamaroSS

iTrader: (3)

Most trans builders and converter manufacturers (including yank) recommed plain old dexron III thats good enough reason to use it.

fortheluckyones

kyle, your right IF your talking about a STOCK transmission. if you modify the tranny at all, that "rule" changes and it is highly recommended to run a synthetic for the extended drain's and for the added "peace of mind".......i'm not disagreeing with you; however, there are different shades of gray involved

WHPLASH

iTrader: (22)

After three rebuilds. Yes, its more expensive and from reading all the posts, no its not worth it in the long run.

No more synthetics for me.

buffman

iTrader: (9)

I have no experience running synthetic in any of my transmissions, but according to one of the builders that resides on the impala forum (the CPT that does builds for the b-car guys) He says no synthetic, use DEX III.. Maybe I'll get a chance to ask him why he feels that way.

EDIT:::
I asked him and he stated that a synthetic is too slippery for a 4l60e. He's torn apart 10,000 mile trans and found nothing wrong but burnt up clutches and an owner that chose to run a synthetic trans fluid.

o2man98

Synthetics can be DEXIII. The AMSOIL ATF and ATD Torque Drive is DEXIII.

jlrz28

iTrader: (7)

I have had Royal Purple in my 2nd and 3rd transmissions. The first one I believe was saved by using synthetic fluid. I lost 6 quarts from a transmission cooler hose coming off the first time and once again I lost 3 from a knick in the hose. The transmission had somewhere around 70k when a band finally broke. I think it saved me. I wouldnt change it. I go and get it flushed once a year (around 20k-25k miles).

fortheluckyones

o2man98 your my hero!! people just dont get it

buffman

iTrader: (9)

Well that's his opinion not mine. He's specifically stated time and time again to use the a non synthetic trans fluid of any kind. Just the standard Dex III stuff. I'll just continue to use what I know works and what doesn't cost me a fortune

ChocoTaco369

what's to get? synthetic ATF has been attributed to causing many 4L60E's to fail. it's too slippery for the transmission. top builders don't recommend synthetic ATF for 4L60E's. why don't you ask yank, chuck or vince? i guess that's the difference between me and you. i trust experienced trans builders, you trust salesmen selling an expensive product. not saying synthetic ATF is a bad product, not saying it's not good for some transmissions, just for a 4L60E, it's been proven over and over that the best ATF is plain old conventional dexron III for both stock AND modified 4L60E's. if you're so set on synthetic ATF, please, run it in yours. if you burn up your clutches, i suggest you keep it to yourself to avoid an "i told you so".

just because it's synthetic doesn't mean it's better.

fortheluckyones

Im not "trusting a salesman selling an expensive product"...im a dealer and sales rep for amsoil as well and i PERSONALLY know the owner AND the owners son of Yank so i know what the "top builders" are saying. i'm not trying to say that my product is the best, period, for every single tranny out there all i'm saying as is o2man98 is that it is recommended to run a dex III in the 4l60's but amsoil's torquedrive atf IS a dex III, so all i'm asking for is why, if they are BOTH a dex III fluid, is one causing premature slippage?!?! i understand that synthetic is slicker than standard ATF but if they are both rated as a dex III then whats the diff???

RooRnZ28

iTrader: (14)

i'm confused... so a no on synthetic? i just flushed my tranny and replaced it with Mobile 1 synthetic ATF. before, it had just regular ole ATF. Then i slapped on my STS kit. After a week of driving after my tune, i lost 2nd... could it have been the synthetic or just the added power? probably both.....

fortheluckyones

most likely it was more the added power more than it was the fluid. my friend's HP turbo t/a made 500.3rwhp on a fully built 4l60e tranny and after one week of driving with the HP kit, his tranny practically exploded as did the next 4l60e that he had built(even better built than the first). hes now the proud owner of a brand new th-400

WHPLASH

iTrader: (22)

Amen. Well said sir. Our transmission builders say "NO" on sythetics.

o2man98

What is to get is that people are saying to run DEXIII but not synthetic. What people do not seem to understand is that when they are calling for DEXIII that it can be a synthetic.

That is all, no hard feelings. I could care less what people decide to run in their applications as long as it provides what they need. I am not here to sell anything, I am here to provide AMSOIL assistance for LS1tech as it is LS1tech.com that is the actual AMSOIL dealer here.

ChocoTaco369

it's not the fact that it's "synthetic" that makes it bad. the problem is it's a more slippery ATF. even if the AMSOIL synthetic is dexrom III based, it's still a more slippery trans fluid. in the case of a 4L60E, no matter how built it is, a slippery ATF is bad. i'm not saying the AMSOIL ATF is bad and i'm not saying you're lying or anything. i'm just saying that for a 4L60E, no matter what the base is, if the product is more slippery, you're going to run into problems with these transmissions.

ChocoTaco369

again, it doesn't matter if it's dexron III based. it's more slippery than conventional ATF. the purpose of a synthetic is to trap particles better, am i correct? it's to provide better lubrication, correct? well, in the case of the 4L60E, the better lubrication an ATF provides is a ticket to a shorter life expectancy.
the 4L60E's, biggest enemy is NOT RWHP. it is RPM's and heat. keep the RPM's down, control the heat and your tranny will last a while. while 500rwhp is a lot for any stock tranny to hold, i'd be willing to bet my membership on LS1tech that if your friend didn't put synthetic ATF in the trans, his transmission would not have died at the time it did. i guarantee it would have lasted longer. again, pretty much any builder out there knows that the 4L60E hates slippery ATF.

fortheluckyones

my friends tranny did not have synthetic in it.

performabuilt

iTrader: (25)

I wonder if there are any published friction cohefficents (spelled wrong im sure)Properties of the various fluilds that would be interesting reading , Im going to do some research into that online surley the information exsist somewhere.