'94 5 speed trans fluid recommendation

[Hooter]

Now that my PMD is fixed, gonna start servicing the beast. Aside from the high dollar GM synchromesh fluid, is there a good alternative to this that I can put in my dually 5 speed with the granny low? On my '92 truck with a V6 and 5 speed, this was the only stuff that would work and shift well. I tried auto trans fluid, Mobil 1 oil, gear oil, etc. I think this trans in my diesel holds a lot and looking to lessen the expense if possible.

[hraney]

When I had my NV5000 overhauled several years ago I was told the synchronizers were nylon and would not hold up w/o the GM fluid. I had some synthetic fluid we used in our OTR truck but the numbers didn't quite match up. I bit the bullet and got the GM fluid to preserve the warranty. On something like the tranny that is going to take quite a bit of abuse, I'd think it would be cheaper in the long run not to skimp on the fluid.

[TAZZ9963]

I use AMSOIL for all my fluids in the truck and I am very happy with my choice.

http://www.amsoil.com/StoreFront/mtg.aspx

[sootjunkie65]

I still like royal purple fluids- theyre expensive around 11 bucks a quart but you get really smooth shifts plus it has the additive in it that the tranny requires

[triplebr1]

i agree with the royal purple, that is what i put in my nv4500, afer it was rebuilt, i love it it shifts smooth, and i have royal purple in evey other gear box too, also if you spend the money now you will not have to change it for a long time so just a thought

[Craig]

The the tranny fluid is a special lube to take the pounding the diesel engine hammers through the drivetrain. It helps obsorb the impact of the high torq low rpm pulses this engine dishes out. My Manual recomends the GM or Castrol product. I have never seen the exact Castrol product on the shelf. My friend with the same tranny in his Dodge could only find it at his Dodge Dealer. I like other brand product (I used to sell Royal Purple products, good stuff), but in this application, personally, I would only use what the manual says.

[synthetic-oil]

Try AMSOIL. NV3500 is amsoil part # MTFQT and it is 6.60 a qt, and the NV4500 is amsoil part # MTGQT for $9.90 a qt
www.syntheticoils.us

Jeff

[grvrjr]

I think royal purple is the best choice also. Amsoil & Redline also make very good synthetic trans. oils also but royal purple in my area is the easiest to find. But any one of these brands will work just fine.

[GM Guy]

On PTO Cover, there should be a decal listing GM and Dodge oil part numbers. We have a Chevy/ Dodge dealer close by, and they only carry the Dodge oil @ $15/qt. don't carry the GM oil because it's about $22/qt and is the same stuff.

We personally use Royal Purple. On Royal Purple Web site, there is a comparison chart. GM PN 12346190 is equivalent to Royal Purple Max-Gear 75w90.

On your V-6 5spd 1500, the fluid is thinner, the Royal Purple equivalent is Sychromax