The 1947 - Present Chevrolet & GMC Truck Message Board Network - Gear Vendors install on a 72 K2500 Things I learned

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Gear Vendors install on a 72 K2500 Things I learned

Figured I would share my experience with the Gear Vendors install on my 72 k2500. There was a lot I learned and even more I took my time on to make sure things were good. This is just a summary for those that might encounter this in the future. Hope everyone is well.

Do's
1) Before you touch anything take "MEASUREMENTS" of your drive shaft. You will need to know the pinion yoke degrees from the Transfer case and also the rear end. ( This is important) you will also need the drive line degree/ angle. You have to have these for reference to compare the new or cut drive shaft too MANUFATURER SPECS SAY THAT THEY BE WITHIN 3° there are plenty of resources to read on this topic. Or you could just ride the lightening and hope for the best LOL. ( There are a lot of great resources online that will help you find your angles, use them if needed)

2) For me I had a small leak coming from my NP205 so I decided to just pull it, get it on the bench and change the gaskets. Once I got it out that snow balled into me completely disassembling it so I could make sure the bearings and gears where good ( They looked great) For those that have not pulled a transfer case by yourself you will have lots of fun!! But since you got it out I would recommend spending the extra couple hours to go through it, clean it and paint it. ( Your gonna have a shiny new gear vendors unit so you might as well have a matching transfer case :)

3) Back to the transfer case. Since you have it out I CAN NOT STRESS ENOUGH THAT IT WOULD BE A GREAT TIME TO ALSO PULL OUT THE TRANSFER CASE TO TRANSMISSION ADAPTER AND REPLACE THE 2 SEALS AND O-RING. These seals and o ring are prone to fail leaking fluid into the transfer case. Some might use ATF for the transfer case also so you might not notice. But those that use gear oil don't want the mix of the ATF. these seals are super easy to change and there is no better time!! Also, might as well paint that to to match the transfer case!

4) The new Gear Vendors unit come with a MSD control box. This replaced the old style control box that they use to send with the GV Unit. These are much more stream line. Follow the directions to a T and you will have no problems with he electrical portion of the install.

5) For those that do not have a 4x4 indicator light. My 72 np205 does not have a light and I believe this wasn't even an option until the late 70s. With this said it is very important that you make sure if anyone else is driving your truck other than you that you disconnect the auto feature on the GV unit. If your gear vendors engages while in 4x4, well you will very much regret it. It will engage in 4x4 if you have not disconnected the auto feature. There is electrical wires from the GV unit that should be hooked up to the 4x4 indicator on most trucks "Safety feature" that automatically disables the system when 4x4 is engaged. For me I am in Alaska and use 4x4 often, however, I am the only one that drives my truck. Just for safety I connected the Auto wires to quick connects. If someone else does drive my truck in the winter I can just disable this feature very easily. If I forget to do that and they throw it is 4x4, I will have the same results as I mentioned above. I spoke to the GV techs for about a half hour and they told me to just do away with the auto feature all together for safety and just run in manual. I really want the auto feature in summer time on long trips and I think I am smart enough and know enough about my truck to make sure is is disabled if I need it to.

Last thing I learned.
When you take your drive line off "Wire wheel" it and clean it before you take it to get shortened. If you do this the shop will more than likely paint it for FREE!. I cleaned mine and took the old u-joints of and then degreased it. Surprisingly when I picked it up they had painted it ( no charge) the guy told me I already spent the time cleaning it and all he had to do was spray it :) and it looks awesome. I also had them throw in Spice LIFE u-joints ( Non-Greaseable for strength) at the same time because they needed to be replaced anyway. they are a little more expensive but well worth it.

If you have a slide yoke on your drive shaft you can still use this, but you will need to have GV send you the fixed yoke for the GV unit and not the slip yoke. Instructions call for 5/8 play in the slip yoke that goes to the GV unit and ties into the drive shaft, however this is for a solid drive shaft and not and slip shaft. Just something to consider. I am about a month out from finally testing this thing out, just welding the mounts for the leather seats on a 2010 Tahoe and then will be all set.

I installed the "Red and Green" indicator lights to the left of my radio and they turned out pretty slick looking.

Hope this can help someone. Its a big purchase and a lot more than just throwing a 700r4 in. I love my th350 and wanted to keep the stock components plus being able to split gears while towing and going through the mountains here in Alaska to my favorite fishing hole is worth way more than just slapping in a r4. Good luck and be safe!