Gear Vendors

[GPSMatt]

Ive got one in my f350 i ran with the turbo 6.9 didnt really toe more than 12k pounds with it beat on it kind of hard anyways i started pulling it apart tonight and found some pieces of gear in the filter bad sign. they say they are good for 25000 pounds and 2000 hp any one else have experience with them? i know Don has one I am gunna fix this one just worried about how its gunna hold up with a hell of a lot more powerful engine once the cummins is all built and in

[MMiller]

FWIW I've heard about alot of GV's dying behind a cummins towing. Granted they are rated for 2000 hp, but are they rated for 600, 700, 800+ ft lbs at 1800 rpms, towing 20,000#? From what I've seen, no. I contend there is a BIG difference between the power from a big block chevy, and a 6BT cummins. One deals with HP at a higher rpm, and one deals out torque at a low rpm. Gasser parts do not seem to last behind a cummins........

I know Don has one, and tows, but how much I don't know, and I suspect that his will fail too, especially with more power on the front side of it.

Michael

[Ace]

That thing is a pretty beefy planetary gearset. I have no doubt it stands up well to whatever it gets bolted to, Cummins included.

OTOH, the oil capacity for the large sump is only a bit more than one and a half quarts. Smallish, by my standards. And they recently started spec'ing Syntorq and the GM equivaleny part# as the preferred lubricant for some reason. I'd be willing to bet most of the GV failures we've heard about can be traced to lube-related root cause. Either not changing the fluid often enough, or using the wrong gear oil.

[flashgordon]

That thing is a pretty beefy planetary gearset. I have no doubt it stands up well to whatever it gets bolted to, Cummins included.

OTOH, the oil capacity for the large sump is only a bit more than one and a half quarts. Smallish, by my standards. And they recently started spec'ing Syntorq and the GM equivaleny part# as the preferred lubricant for some reason. I'd be willing to bet most of the GV failures we've heard about can be traced to lube-related root cause. Either not changing the fluid often enough, or using the wrong gear oil.

I'm with Ace on this one. I thing they are plenty strong for even a cummins.............and you can get way stronger one then the base model that I'm running.

I truly thing that most failer are from people thing that is a auto and you don't need to worry about it for 50 to 100,000 miles

As Ace said there is vary little oil capacity and and need to be change often.

Hay Ace, what oil are they recommending since the recipe has change on some of these oil .

I'm probably past do for a oil change on mine

Alto i did check it yesterday and it still look clean and was full.

Flash.

[GPSMatt]

I think the problem on mine was a trip to texas i made started leaking and i only figured it out when it wouldnt shift. Mine is a divorced unit and has atleast 150k on it.

[Ace]

There was an addendum came attached to the owner's manul with mine listing both the Mopar and GM Part#'s for Syntorq. I even called them to confirm it hoping maybe it was a mistake, because that stuff is expensive. They said the reason was because their testing found it shifted smoother. I don't believe it for a second. I think their testing proved it would get them out of warrany without ever being changed in most cases.

[GPSMatt]

how often do you need to change the fluid in them?

[Ace]

The recommended interval is only 5,000 miles. I'm thinking about installing an external filter and cooler with a circulation pump similar to what I did with the Getrag, mainly to increase the fluid capacity and service interval.

[GPSMatt]

yeah the filter it has isnt really that good i need to tear into mine more now to see where the chips of gear came from

[DTanklage]

what fluid you put in them definitely determines how hard they will shift

i remember 20 years ago GV recommended atv - if ya can believe that

then, I think they started rec motor oil

I don’t know, I will run anything in mine

I don’t remember what I put in mine when i first installed it but man, it shifted way too hard

made it a nightmare to drive

now I just use the stalube 90 wt (syn)

this unit is about 2 yrs old and has been thru hell

when you are on it at 3 grand, maybe 3200, in 4th gear and you pull the red lever - watch out

whole fregin truck jumps

I mean it pulls hard

if you are racing someone that is basically as quick as you that one shift is good for 2 truck lengths

and those two lengths happen almost instantly

I have a friend in oregon that rebuilds them really well, and for a good price if interested

don

[GPSMatt]

do the internals differ? mine is real old school its a divorced unit the previous owner said was put in in the 80s

[Ace]

what fluid you put in them definitely determines how hard they will shift

Lighter fluid, easier shift, heavier fluid, harder shift. Pretty much goes for just about anywhere teeth are gnashing in a gearbox. That's why Syntorq is an ideal compromise in some cases. It's a fairly light (around a 50w, as I recall) fully formulated synchromesh gear oil. It was deveoped by Castrol under contract to New Venture for the NV4500 specifically to hold up in there behind the Cummins. Great stuff. Wish it was a little less expensive.

[DTanklage]

the GV is actually a auto trans

[Ace]

I'd call it more of a hybric trans. Or maybe a mauto. How about amual?

[flashgordon]

what fluid you put in them definitely determines how hard they will shift

i remember 20 years ago GV recommended atv - if ya can believe that

then, I think they started rec motor oil

I don’t know, I will run anything in mine

I don’t remember what I put in mine when i first installed it but man, it shifted way too hard

made it a nightmare to drive

now I just use the stalube 90 wt (syn)




this unit is about 2 yrs old and has been thru hell

when you are on it at 3 grand, maybe 3200, in 4th gear and you pull the red lever - watch out

whole fregin truck jumps

I mean it pulls hard
if you are racing someone that is basically as quick as you that one shift is good for 2 truck lengths

and those two lengths happen almost instantly

I have a friend in oregon that rebuilds them really well, and for a good price if interested

don

I remember the fist time i shifted my GV in at free way speed in 5th with no load on the truck at all.
flip the switch.. I look into the mirror expecting to see part and pieces shelling out from under the truck................no parts, let the clutch out again, step on the gas all good.

I eventually learn that under hard acceleration it was a good kick in the pants but with out a load..........push clutch in, shift into over drive THEN let the clutch back out.

I just replace the side and spider gears on my 70 couple of week ago, took a lot of the bang a way.

Also the fluid that there instruction recommended is the stuff that they don't now because of the harshness of the shift.

Flash