94 fbody gear fluid??

[Firehawk409]

Well from the total "abuse" of my car just being parked for the past year or two my diff started leaking.

So it looks like I'll have to take the cover off.
It has GM motive 4.11 gears and I am curious as to what everyone recommends I should use. I think 75w90 is what it calls for. The car does not see any street/track time anymore. For the most part it stays parked. I have no idea of when I'll have it back on the road but I still don't want to skimp out. Is there a timespan of how long gear fluid lasts...time wise? For example if i change the fluid now and a year later its back on the road would I have to change it again?

I do still have my PC membership with Amsoil. Was thinking of just going with that.

Oh btw, I do have a 6speed which tends to be murder on the rearend. Not sure if that accounts for anything.

Omar

 

[MGregoir]

75W-110 Amsoil Severe Gear.

 

[JohnBrowning]

Why is your Fbody just sitting? It is not a Stanley Steam get out their and drive that thing! If you are going to store it you normaly put the car on jack stands to take the weight off the axles. If I where you I would add dino gear oil and auto-rx to those axles. I have no idea though how any gear lube is going to anything if the car is never driven. Oils do not do anything just sitting in the sump they have to circulate. Seals dry out because their is no oil on them. Haveing the oil in the sump does nothing if it does not circulate.Syntetic in a car that is not driven is like wipeing your butt before you poop it just does not make any sense at all. A synthetic base stock is not going to protect from rust any better then a dino. You need to consider doing some proper storage if you want to keep this thing as a garage queen. Seal failure and rust issues are only going to get worse in the long run!

While I hate garage queens and trailer queens I wwish you the best of luck! Their are specialty products on the market just for storeing hot rods and older cars. Molakule used to make and market some on this site. You might try contacting him. Generaly I do not see car's as investments they are consumables so they are best when they are on the road. If you like a particular vechile you drive it till you wear it out then you make it a project vechile and restore it to all it's glory! Then you trie really hard to wear it out again before you die!Gold,Platnium,Paladium,Rhodium,Oil,Pork Futures etc..... those are investments.In fact the only thing that I hate more then a nice car just sitting is people that think their Beanie Baby collection is going to put their kid through college!

P.S. If anyone has an FBody just sitting around if they are interested in giveing to me or willing it to me I will happily come and get it and give you my personel info for the legal forms. I promise it will be well cared for and pampered and at least once a year it will go auto-crossing with me and then to the track!!! I use quality wax,oiland interior care products!!!-John

 

[Firehawk409]

LMAO! bro you are way off on this one. Trust me this fbody is by no means a garage/trailer queen. I drove this thing for over 10years straight..total abuse, daily driver while in colleg, nitrous for a little while, and before it got parked at 130k I put cam that loves to see 6500rpm shifts. All on a stock internal lt1 that is still kicking.

The reason i dont drive it. Well I just dont have the funds for it right now. I hate to sound cliche, but getting married has slowed the modding on it and I can't justify spending the money on it like i used to when trying to put the wife through school and TRYING to save for a house. Good news is this fall is my wife's last semester which means she will be getting a job. Hopefully then I'll have it back on the road for some fun.Thinking about trying my hands out on auto x. Oh might i had I also have a company car. So no need to daily drive really.

So in a nutshell i want to put something good in it now in case i do get it back on the road. I dont want to have to change it again. The guy who did my gears told me to just stick with dino gear fluid and change it every 20 to 30k. Maybe i should stick to that?

 

[dailydriver]

IF you have an Auburn diff in it (which if I remember correctly I think you do stock unless you changed it out?), absolutely stick with a dino/mineral based gear oil, despite you being waaayyy out of warranty.
Auburn themselves will tell you the same.

 

[Firehawk409]

i dont really remember what diff i have. When i got the gears the guy sold me a stock diff with it, but I don't remember if its an auburn. Anyway to tell if it is? Maybe thats why the guy who did my gears told me to just stick with dino oil.

 

[JohnBrowning]

Well I am glad I was way off!! In Michigan especialy while working for GM I saw more Garge and trailer queen Corvettes then I care to ever see again. In my book it is a complete and total crime to not drive a car. Even Jay Leno drives al the priceless cars in his collection. If you can not afford to drive the vechile then you could not afford to buy it in the first place... Not talking about you either. I have seen so many cars just going to waste. You would think they where pagan gods placed upon an alter to be worshiped and looked upon but never touched!!! I mean it is really sad. I always had to pretend to understand since all these people where basicly high dollar GM executives! Can you imagine hemeticly sealing your wife in a case just to look at her and never touch her or do anything with her???What would be the point! So I am glad you have driven the tar out of it....Now when you get the time and money you can restore it and do it all over again!

 

[Firehawk409]

thats pretty much the plan at the moment. Once i spend half of eternity to save up for a garage with an attached bedroom, living room, kitchen and bathroom(wife demand's the last 4), then I'll spend the other half of eternity into restoring it.lol

 

[aquariuscsm]

Originally Posted By: Firehawk409
i dont really remember what diff i have. When i got the gears the guy sold me a stock diff with it, but I don't remember if its an auburn. Anyway to tell if it is? Maybe thats why the guy who did my gears told me to just stick with dino oil.


Just out of curiosity,why would dino be recommended over synth?

 

[Firehawk409]

honestly i dont really know. I just remember him telling me "just use regular gear oil and change it every 30k" I took his word for it since he drives a 95 z28 that is one of the fastest n/a lt1s that he built himself.

 

[dailydriver]

Originally Posted By: aquariuscsm
Originally Posted By: Firehawk409
i dont really remember what diff i have. When i got the gears the guy sold me a stock diff with it, but I don't remember if its an auburn. Anyway to tell if it is? Maybe thats why the guy who did my gears told me to just stick with dino oil.


Just out of curiosity,why would dino be recommended over synth?


The cone type clutchpacks in the Auburn, and the carbon fiber (and the steel in the older ones) clutchpacks in the Eaton diffs just DO NOT work right in synthetic fluids.

In fact, IF one was still under warranty and had a problem, then sent the diff in for warranty work/exchange, BOTH companies would deny the claim if synthetics were used (YES, they do a UOA on the fluid!!!), since the owner (new/original owner at least) was expressly told NOT TO USE synthetic gear oils in these units!

 

[Firehawk409]

well anyone recommend one dino gear fluid over the other?

 

[Firehawk409]

anyone??

 

[dailydriver]

^^^^
The Schaeffers #209 is pretty much top of the heap, but IF you cannot find or get it the Torco RGO is not too far behind that excellent stuff!

 

[Firehawk409]

man the closest place that deals with Schaeffers is like 2 hours away. Don't think I know of any place local that sells torco either. As much as I'd like to try this stuff out I think im gonna have to pass. It's not worth the hassle and money for me right now being that it does not get driven. I used castrol for the past 30k with no problems, maybe i'll just go back to that.

Question....if we are not supposed to use synthetic then how does amsoil and other syn oils reccomend it for our rearends? I'm sure they tested it. When i first got my car I did use mobil 1 syn gear oil for a good 50k. My stock gears looked pretty dang good for the abuse i gave the car. Though i never put slicks or drag radials on could be a reason of why it lasted so long.

 

[JohnBrowning]

A lot of people do not understand synthetics and would rather stick to what they know. It is not like dino is going to kill the thing so it is not bad advice it just is not acompletly accurate or the best advice! I know I do not think it is worht the money to put a synthetic in a vechile not being used. If it is just sitting their why use a synthetic it is not going to offer any added protection for storage so it is money wasted!

 

[Firehawk409]

yeah i think i'm just gonna stick with a decent "cheap" dino oil for right now. The only reason im doing this is cause of the leak which im sure will be fixed after replacing the fluid and laying down some RTV on it. Once I go back to driving it then I can make use of the drain plug that came with the aftermarket cover i have and put something better.


edit: Just noticed i got my vet avatar.

 

[dailydriver]

Originally Posted By: Firehawk409
Question....if we are not supposed to use synthetic then how does amsoil and other syn oils reccomend it for our rearends? I'm sure they tested it. When i first got my car I did use mobil 1 syn gear oil for a good 50k. My stock gears looked pretty dang good for the abuse i gave the car. Though i never put slicks or drag radials on could be a reason of why it lasted so long.


Some of it may stem from the fact that the synthetics are perfectly A OK for the latter year ('99-02) Zexel-Torsen diff equipped f bodies. (Synthetic gear oils were supposedly the factory fill on these units.)
These being worm gear type units as opposed to cone or clutch pack diffs.

Actually GM probably did not test synthetics in the Auburn diffs, or if they did, they found problems which is why they (and Auburn) only allow dino based in these units.
I seriously doubt that Amsoil, let alone the majors test their fluids in every type/style/brand of differential out there!!

My 4.10s have lasted a VERY long time despite some very hard, prepped track launches on drag radials (albeit "only" Nittos).
Some say this is due to proper initial setup combined with almost maniacal gear oil change frequency (like every 5K miles!

), even though I used a (great) dino fluid (Torco RGO).

 

[Buffman]

Eaton LSD units specifically state to use a conventional rear end fluid only with their units. At least their aftermarket units anyways.

 

[BayouTodd]

Originally Posted By: dailydriver
Originally Posted By: Firehawk409
Question....if we are not supposed to use synthetic then how does amsoil and other syn oils reccomend it for our rearends? I'm sure they tested it. When i first got my car I did use mobil 1 syn gear oil for a good 50k. My stock gears looked pretty dang good for the abuse i gave the car. Though i never put slicks or drag radials on could be a reason of why it lasted so long.


Some of it may stem from the fact that the synthetics are perfectly A OK for the latter year ('99-02) Zexel-Torsen diff equipped f bodies. (Synthetic gear oils were supposedly the factory fill on these units.)
These being worm gear type units as opposed to cone or clutch pack diffs.

Actually GM probably did not test synthetics in the Auburn diffs, or if they did, they found problems which is why they (and Auburn) only allow dino based in these units.
I seriously doubt that Amsoil, let alone the majors test their fluids in every type/style/brand of differential out there!!

My 4.10s have lasted a VERY long time despite some very hard, prepped track launches on drag radials (albeit "only" Nittos).
Some say this is due to proper initial setup combined with almost maniacal gear oil change frequency (like every 5K miles!

), even though I used a (great) dino fluid (Torco RGO).


Just to chime in on auburn posi units:
My 99 hawk ls1 has one and my unit was making noise, well some idiot dealership changed the fluid and ONLY put in dino fluid and NO GM posi additive...so I flushed it our, added fresh dino and 2 bottles of gm posi additive and viola, nice and quiet!
So don't forget the gm posi additive, I have the p/n if anyone needs it and I get mine from gmpartsdirect.com