[JCurtis]

Ok, I'm switching over to Synthetic Oil because It sounds like the way to go especially for plowing.

But my main question is is it worthwhile to go to synthetic Transmission Fluid in my GMC?

I know there are pros and cons I read them somewhere, but I want it straight from the users mouth ! Anyone running syn. trans fluid in their trucks? Is it worth the expense.

Oh and I will be installing a pod Mount Trans Temp gauge, and possibly a deeper pan.

 

[wyldman]

Synthetic fluids do have some benefits over conventional oils.I usually recommend them for fluids that don't get changed very often,like transfer case,and differentials.

With transmission fluid,I prefer to change it every year,and do a complete trans service,with a new filter.Using synthetic this way can get very expensive.If you want to spend the extra $$$,then go for it.You must also be careful as well,as some OEM's are very picky about what goes in,and can give you a hassle if a warranty problem.Make sure whatever you use is OEM certified.

The conventional oils and fluid have come a long way in the last few years,as the OEM standards keep getting tighter.Using a newer oil which is backward compatable(as most are,but not all) will give you added protection as well.

 

[Dockboy]

Jeff,

Here are some of my personal observations with syn tranny fluid. Now granted this was with a Ford 4R100, so I don't know if the same would apply to a Chevy.

I put Mobil One in my truck at about 30k mi. The temps dropped abot 10 deg. But the tranny felt like the clutches didn't grab as well as they did before with dino. At 60k mi., I changed back and could definetly tell the difference I liked the dino much better

I recently had my tranny rebuilt by Brians Truck Shop . He build indestructable Ford trannys:burnout Brian uses Schaeffer's Oil . I asked him why he liked it so much and he said it's because it has all the good properties of syn but with better friction.

 

[Joey D]

I run Mobil 1 in my trans, the whole truck, and I agree with Dockboy. It does run cooler but the shifts don't seem as firm as they did before. I am going to try the Schaeffers

 

[ratlover]

There have ben people that have issues with some fluid being too slick. Its not really the fact that its synthetic, its the fact that what ever brand's additive package is too slick. Amsoil developed a replacement for the transdyn(allisons synthetic fluid), people were getting thier trany to slip with the amsoil synthetic dextron.

In my allison I would only use regular dino dextron(actually what I am using) or the Allison transdyn(or how ever the heck you spell it)

The only benifit I see for synthetic fluid in a trany is that it will withstand heat better. This can be a big deal since trany fluid life is directly proportional to how hot you get it. Personaly though I plan on using regular dino and changing often.

If you switch to synthetic you have to get all the dino out or you arnt realizing the synthetic benifits. Your only as good as your weakest link. The good old yanking of the cooler lines is the best way IMO on most chevy tranys and the alli

 

[ratlover]

3 minute one edit :headwall I need to read faster

More on amsoil stuff:

I'm not nocking them in particular just trying to illustrate that its the additive package not the base oil

(so they basicly made a grippier version of what they had or through a new lable on what they were selling, I dont know, I dont have any experience with this stuff) It wasnt the synthetic trany fluid, it was thier additive package was too slippery. Ford dino oil is the same base as dextron but its more grippy, its all in the additives.

 

[John DiMartino]

OK, I personally use cheap Dextron 3 in my Rams trans.I am a Sheaeffers oil user too.I use Shaeffers D3 in all own trucks,and Dads.We use Shaeffers exclusively. Buy most of my customers run cheap dextron 3,and change it often,or amsoil universal ATF/racing ATF. We use a 50% mix of universal ATF,and racing ATF,this gives the same feel and fricyion as stock,but with benefits of synthetic. My personal feelings are for a plow truck,use reg ATF,change it often.For tow trucks that rack up miles fast synthetic is the better way to go,the planterys and end play show very little wear on those running the amsoil,and they can run extended drain intervals,which is helpful when running a lot of miles.a plwing tranny is going to get beat either way,but if cost is no object .if run amsoil at the 50/50 mix.

 

[Joey D]

John, Great article in the Snow mag

 

[teeca]

if you want a good shift, without going into the transmission, go to the dodge dealer and get there trans fluid, its kicks a**! as for synthetic oils, i run them in all my engines, as for trasmissions, i'm a believer in hard, fast shifts. 1 cool thing about synthetic oil is it doesn't burn, so if your selling a vehicle that smokes, put mobil 1 in it and worry no more. oh, and synthetic oil is not really synthetic, it's just the way (oil) it's prossesed.

 

[CNY Joe]

I have experimented with the synthetic fluids. I prefer not to use them as they cost more and with the amount of miles (about 25,000 per year) I put on my truck. I like to change the fluids on a regular basis.JMO

 

[ratlover]

oh, and synthetic oil is not really synthetic, it's just the way (oil) it's prossesed.

Some is actually made of completely synthetice base stock. Some oils advertise as synthetic but just use altered dino oil as thier base. Shell rotela synthetic comes to mind. Group 5 oild I believe are full synthetic....group 4's are processed dino oils that are called synthetics.....I think going off memory here. I got way to many #'s floating in my head and I'm probably jacked up here

 

[teeca]

sorry, i was refering to auto/truck oils. they all have crud oil in them. if they didn't, your engine wouldn't hold a drop of oil, it would all leak out. seals/gaskets used in the vehicle industry car/truck are made to react to oil, swell slightly, and maintain there softness.