gear splitter?

[fishmaster]

i have been looking at getting one of gear vendors gear splitters for my 84 gmc and was wondering if anyone knew anything bout them? how hard are they to install and how much do they improve the trucks gears?

 

[kickdeez]

I have been putting some thought into this idea as well. I am not ready to pull the trigger yet, but when I am, I think I will go with the Advance Adapters Ranger Torque Splitter for my SM465. The Gear Vendors unit is twice as expensive as the AA unit. Regardless of which one you go with, I would imagine the installation difficulty is relatively the same. If you can remove and re-install a transmission, I would bet that you could install one of these overdrive units. Both of them claim over 20% gains in fuel efficiency due to lower RPMs. The GV unit appears to replace the tail-housing of your existing transmission. Not sure what the dimensions are, or if it lengthens your drivetrain. But the AA unit actually bolts on between your bellhousing and transmission. It is a little more than 7" long, so this will require modifications to both front and rear driveshafts, as well as tunnel modifications (likely). I believe the GV unit is electronically controlled by the push of a button. The AA unit uses a standard mechanical shifter linkage.

Don't know if any of this helps you, but I am interested to see what you end up with and interested to see what others have to say about the GV splitter. Good Luck!

 

[fishmaster]

thank you for replying, it does help me kind or understand what i'm looking for. what web sites have you gone to to find other options? i can only the one for my truck on the gear vendors website and no where else.

 

[MadOgre]

I would think for the large cost and increase in transmission length that it would be whole lot easier and more common sense to just go to an over drive transmission. ???

sm465 to either an NV3500 or 4500

TH350,TH400 to a 700r4 or a 4L60e or 4L80e

 

[kickdeez]

What kind of transmission do you have? What do you use the truck for? What kind of driving do you typically do with it?

In my case, I have a 3 speed + granny low SM465 manual. I use my truck for towing, so I want to keep the manual, and the SM465 is known for its strength and reliability. I have heard that the NV4500 is a good transmission, but you would be looking at the same problem going from the SM465 to the NV4500, which is the dimensions are not the same. So you would still be stuck with drive shaft modifications, relocating the cross member, etc. Additionally (in my case) I would have to get a completely different bellhousing, and maybe even clutch kit (I havent looked that far into it). Not to mention, a new transmission is more expensive than the Ranger Torque Splitter. The Gear Vendors option is about equivalent to a new transmission, maybe a little more expensive.

Im not extremely well versed in the world of GM automatic transmissions, but if you have an automatic, i think for the cost of the gear vendors unit, you could probably put a pretty well built and bulletproof 4L80E in your truck and be in a good spot. My buddy is getting ready to purchase a Monster Transmission's 4L80E for his 6.5 TD dually which he uses for towing. And i believe it is close to half the cost of the gear vendors overdrive unit.

 

[MadOgre]

Well also consider the ease of use which can become a PITA to operate with an auxiliary gear box. I guess I just assume everybody with a K truck has it lifted LOL. That's the first thing I have done to all of mine. Which leaves you with a short drive shaft. Going to an OD transmission is usually only 1-2" longer vs a whole additional gear box which seriously increases drive line angles.

 

[fishmaster]

honestly i cant tell you all the specifics bout my truck cause i'm not really a big gear head type person so here's all i know bout it, it is a 1984 k1500 gmc 6.2 liter diesel. and i think it has a 4.10 rear end, it has granny-4th and tops at 55mph. I manly use it for hauling big loads of hay, wood, coal, and fencing supplies, other than that i use it to get to school. i was looking into this to see what would be a better option for me, getting the gear vendor or buying and instaling a 5 or 6 speed trani in it.

 

[MadOgre]

Well you have low gears with 4:10s which is good for the ol 6.2. I see the need for an OD as well lol.

So with an additional gear box you will have to drastically shorten your rear drive shaft any way and lengthen the front. Or the OD only works in 2wd which in any case you still need to drastically shorten the rear drive shaft.

How strong is the auxiliary gear box as the OD in top gear with force being applied to haul hay is now going to be heavily stressed.



Going with an NV4500 will give you a gear box that was designed for doing just what you are doing and only minimally shortens the length of your rear drive shaft. The front will need to be lengthened but there is a long yoke for the CV front shaft that gives you another 1.5 inches in length. Now you would have a setup that was stock for 1 ton trucks from the factory.

@marks86 installed one in his and I believe he is in love with it lol

 

[Daveo91Burb]

A few things to bring up in this discussion. The Ranger OD only works with manuals and I think just the SM465 for our trucks. You can get adapters to make the GV work with just about anything, auto or manual, but they are specific adapters for each tranny and they are not cheap. Ranger goes in front of the tranny so it works in 4wd. GV goes behind the t-case so only works in 2wd. Finally, Ranger uses a stick for shifting so split shifting is challenging when upshifting main tranny and simultaneously down-shifting the aux tranny. But it can be done - there are some you tube vids of people doing it. GV uses a push button or similar so it can be installed on the shifter and shifted like a 2 speed rear end on bigger trucks. But that's all I know - just from reading about these through curiosity. My truck has a 4L80e so I think I'll just go with that and call it good!