ridgerunner97
03-08-2015, 10:24 PM
Well before we get down to brass tacks, errr bronzesynchronizers a little background. I have an 02 Dodge 2500 pickup with the desirable High Output options package which mainly consists of the Cummins diesel with the 245hp 505ft lbs of torque spec, NV5600 6spd transmission and Dana 80 rear axle with disc brakes. I decided to send the truck in to Greensburg Machine to have them install a new South Bend clutch since my stock style clutch was slipping. I have had some oil on the bottom of the bellhousing so I assumed the rear main was weeping (it is a Cummins afterall) and I gave them the go ahead to do that while the transmission was slid rearward to install the clutch. The NV5600 is a very stout six speed manual transmission with an integral aluminum bellhousing, cast iron main case, and cast iron transfer case adapter. It weighs nearly 500lbs by itself.
I got the call Wednesday from Mark at Greensburg Machine that my input shaft on the transmission was junk and we had to figure out what we were going to do. The input shaft on the NV5600 is a massive piece that is 1 3/8” in diameter on my spec truck. What happens is the factory flywheel has a needle bearing inside of it that the snout of the input shaft rides on. This needle bearing disintegrated due to time, poor design, and my truck having 237,000 miles on the odometer. The hub in my clutch was also torn out and due to the needle bearing failure I’ve lost the front seal in my transmission allowing the clutch to become oil soaked by transmission oil, NOT the rear main seal like anticipated. The wobbling allowed my input shaft snout to be worn out of spec.
The NV5600 is a real bastard of a transmission. Everything comes out the rear of the transmission including the input shaft which is the last thing to be removed, which you guessed it warrants a COMPLETE disassembly to retrieve it for repair. A new input shaft runs anywhere from 240-500 dollars. Runout on my worn input shaft varied from .747 down to .734 O.D. Spec is .750 I.D. on the revised South Bend sealed ball bearing in the new flywheel. The tentative plan is to disassemble the NV5600 to retrieve the input shaft, send it to a friend to get machined down to an even spec then have a bushing with a wall thickness of .125 heat shrunk to the now uniform input shaft snout to achieve a proper fit in the .750 I.D. ball bearing.
406407
On to the tear down! This transmission weighs almost 500 lbs. It consists of an aluminum bellhousing that is integral to thetransmission, a cast iron main case with shift tower, and a cast iron transfercase adapter.
408
First steps are pretty clear, you must remove the boltsholding the transfer case adapter onto the main case and utilize a puller, in my case a 3 jaw I had laying around, a 2 jaw would be superior to remove theadapter. Underneath the adapter resides bearings, gears, and reverse gear and shift fork. Remove all of the loose parts and your readyto lay this behemoth horizontally again to remove all the bolts in the bellhousing.
409410
411412
More to follow tomorrow, i'm tired of this computer acting up...
I got the call Wednesday from Mark at Greensburg Machine that my input shaft on the transmission was junk and we had to figure out what we were going to do. The input shaft on the NV5600 is a massive piece that is 1 3/8” in diameter on my spec truck. What happens is the factory flywheel has a needle bearing inside of it that the snout of the input shaft rides on. This needle bearing disintegrated due to time, poor design, and my truck having 237,000 miles on the odometer. The hub in my clutch was also torn out and due to the needle bearing failure I’ve lost the front seal in my transmission allowing the clutch to become oil soaked by transmission oil, NOT the rear main seal like anticipated. The wobbling allowed my input shaft snout to be worn out of spec.
The NV5600 is a real bastard of a transmission. Everything comes out the rear of the transmission including the input shaft which is the last thing to be removed, which you guessed it warrants a COMPLETE disassembly to retrieve it for repair. A new input shaft runs anywhere from 240-500 dollars. Runout on my worn input shaft varied from .747 down to .734 O.D. Spec is .750 I.D. on the revised South Bend sealed ball bearing in the new flywheel. The tentative plan is to disassemble the NV5600 to retrieve the input shaft, send it to a friend to get machined down to an even spec then have a bushing with a wall thickness of .125 heat shrunk to the now uniform input shaft snout to achieve a proper fit in the .750 I.D. ball bearing.
406407
On to the tear down! This transmission weighs almost 500 lbs. It consists of an aluminum bellhousing that is integral to thetransmission, a cast iron main case with shift tower, and a cast iron transfercase adapter.
408
First steps are pretty clear, you must remove the boltsholding the transfer case adapter onto the main case and utilize a puller, in my case a 3 jaw I had laying around, a 2 jaw would be superior to remove theadapter. Underneath the adapter resides bearings, gears, and reverse gear and shift fork. Remove all of the loose parts and your readyto lay this behemoth horizontally again to remove all the bolts in the bellhousing.
409410
411412
More to follow tomorrow, i'm tired of this computer acting up...