Well, it's time to change out the fluid again and I wanted to know what the best combination of fluids are out there.

I got GM Motive 4.10's which have a small whine at 60 mph. I've heard everything from using a synthetic in combination with the GM additive to using a synthetic alone, to just using a dino with the GM additive and dino alone.

I was hoping to clear up the confusion. <img src="images/icons/confused.gif" border="0">

 

I talked to the owner of the trans shop that put my converter/Transgo/cooler in and he said use the regular Dexron III in the trans but use synthetic in the rearend. I also e-mailed Tom Izzo @ LS1Speed.com and he also seemed to suggest using synthetic in the rearend. Better cooling and better lubrication. I just ordered 2 quarts of Redline Synthetic to put in when I get my T/A Girdle. <img src="images/icons/smile.gif" border="0">

 

On my stock, I just used dino and never had any problem. In my 12 bolt I use dino + GM additive.

If you have whine, a heavier viscosity oil my help quiet it down.

 

I had used Redline in my last two cars and even tho I never had a problems when the dealer recently changed the gears, they put in GM+additive and it grabs alot better now. Even around corners ... before sometimes I used to get the one wheel wonder spin... now it grabs like it should. I`m using the dino stuff from now on.
Definate improvement on my car.

 

Honestly it's not that big a difference for our intended usage levels. If you were running silver state, etc. then synthetic with a rear end cooler for sure!

If you have a locker Dino oil tends to be "quieter" than normal oil. If you have a posi make sure you use the posi additive. Other then that I would just go with what you feel comfortable with (just stick with major brands).

Chris

 

Its good to hear that the dino with GM additive is a good bet. I've been doing that all along except when MTI changed out the gears, I think they put in a Castrol synthetic. I'll probably go back with the dino+GM.

 

I went with Royal Purple and GM additive for extra measure when I installed my TA Girdle and stud kit.

I can say that rear end "clunk" was reduced considerably. As a matter of fact, I can't remember the last time I heard it clunk. <img src="images/icons/smile.gif" border="0">

 

[quote]Originally posted by WEASEL:
<strong>I went with Royal Purple and GM additive for extra measure when I installed my TA Girdle and stud kit.

I can say that rear end "clunk" was reduced considerably. As a matter of fact, I can't remember the last time I heard it clunk. <img src="images/icons/smile.gif" border="0"> </strong><hr></blockquote>

That's great to hear WEASEL. Ever since I got my converter installed the 'clunk' is annoying as hell. Just ordered a T/A Girdle w/ stud kit as well as some Redline fluid and the GM additive. Hope that takes care of it. <img src="images/icons/smile.gif" border="0">