Subject: TC disassemble instructions Part 1
I am going to be alittle generic about the Jacking and securing the vehicle, and some other steps, you should be able to do that if you are going to attempt theis pump upgrade. I have been struggleing with cut and paste of pictures to include with this instruction, so if need be I will include the disassembly proceedure, and reassembly proceedures along with the Transfer case inspection instructions, so use as needed. NOW LET'S GET STARTED!
1. Find a level surface, and jack and secure the vehicle, I used jack stands in my driveway, so you do not need a lift to do this.
2. Using a 11 mm wrench, remove the bolts that hold the U-joints in the the reaer end and the front end. Have some tape on hand to tape the u-joint so the cups do not fall off. After you remove the bolts, cut the band clamp on the rubber boot on the front driveshaft where it goes into the transfer case. Remove the driveshafts by sliding them out. I reinstalled the bolts loosly in the U-joint area so they would not get lost.
3. Drain the transfer case. I say to do this or you may end up wearing some of the fluid when you fumble the case around trying to get it out.
4. Locate and disconnect ALL of the electrical plugs that go into the transfer case. The sppeed sensor ion the tailshaft, and the encoder motor. Also trace the wires and locate where they are held out of the way by brackets, and make sure the wires are disconnected from the brackets as needed if the brackets are attached to the transfer case. I pushed the wires aside on the drivers side up on the frame.
5. Find you a good piece of wood or something that will cover almost the entire area of the transmission pan, you will be jacking on this area, so be careful and do not get carried away when jacking. Now jack a floor jack up to the transmission pan with the wood between the jack and the pan, do not put to much pressure on it, the mount is still attached. Get used to that jack being there, it will be there till cross member is back in place.
6. Remove the nuts that attach the transmission mount to the cross member, and jack the jack that is under the transmission pan untill you see the transmission move and is off of the cross member.
7. Remove the bolts that hold the cross member in the frame, and remove the cross member out of the way. Now remember the transmission is resting on the jack and the piece of wood that is under the transmission pan.
8. Now lower the jack SLOWLY until the transfer case is restin on the torsion bar cross member, this will make it easier to get to the top nuts that hold the t-case on the tranny. Now is a good time to find the VENT line that is on top of the t-case, and disconnect it from the plastic elbow, be careful, it is plastic, and can break.
9. There are 6 nuts on studs that hold the transfer case on the tailshaft of the transmission. With the transfer case resting on the torsionbar cross member remove the top 3 nuts using a open end wrench, you may be avble to use a socket, but I did it with a openend wrench.
10. Now jack the jack up until the t-case looks to be about to touch the bottom of the truck, and lock it down. Now remove the bottom 3 nuts off of the studs, now the transfer case is being held in place by gravity resting on the studs.
11. Now if you are strong enough, or have some specisl jack, get under it and slide it to the rear and off of the splines in the transmission shaft, and it will rest on the torsionbar cross member, BE CAREFUL, it is still unsteady untill you get it on the ground. I would assume this to weigh about 75 lbs, more or less, I did not weigh it.
12. Wrestle the case out from under the truck, I lowered it down by Armstrong, onto a creeper, then wheeled it out from under the truck. Now we are ready to get to the meat and potatoes of what we are out to achieve.
13. Find you a good working surface, I used a piece of wood on my tailgate, using deadblow hammers as chocks to steady it in whatever position I wanted. Now time to follow the transfer case disassembly proceedures, I only used the steps I needed, I did not remove the encoder motor or other parts, I only removed what was needed. So step 14 will be the instructions for disassembly of the transfer case, and then I will lay out what I did.
Remove the rubber plug on the transfer case tailshaft housing, and remove the speed sensor that is threaded into the tailshaft housing.
View attachment 35120
View attachment 35121
Now remove all of the case bolts, BE SURE TO MARK WHERE THE BRACKETS GO that are held on with some of the case half bolts.
View attachment 35123
Now with a pair of flat tipped snap ring pliers that will expand the ring, insert the pliers through the oval hole in the tailshaft housing that the rubber plug was blocking, and expand the snapring that is in there, this may be alittle difficult, but work with it, and pry on the reluctor wheel through the speed sensor hole with a screwdriver, to pry the case halfs apart and get the snapring to release the rear case half.
[/ATTACH][/ATTACH][/ATTACH]
When you get the case halfs apart, remove the snapring holding the bearing and reluctor wheel on the tailshaft, and remove the bearing, and reluctor wheel.
[/ATTACH][/ATTACH]
Remove the pump housing assembly, you will have to pull the oil pump pickup tube out of the housing, it is only held in place by a O-ring. Remove the Torx Screws T-15 holding the pump housing together, they are not very tight, and then separate the housing, this is a gerator type pump, sothere is not but 2 parts inside the housing, make sure to reassemble the new pump housing the same way you disassemble it.
[/ATTACH]
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Now is the time to clean the inside of the transfer case, if it does not look clean, I used a can of degreaser and hosed down the inside of the transfer case and rinsed with the old garden hose. Used compressed air and blew out the excess water, and then removed the oil pump pick up and cleaned it and made sure there were no obstructions, and removed the magnet and cleaned it as well. I then reassembled everything in a reverse order, I spoke with Eric at Merchant Automotive about torque on the torx-15 screws, and we both agree that just get them good and snug/tight using BLUE locktite.
[/ATTACH]
Now reinstall the pump housing onto the tailshaft, followed by the reluctor wheel, the step on the reluctor wheel goes toward the pump housing. Then install the bearing, the groove is to face the end of the shaft, or up if you have the case pointing up. Install the snap ring into the groove to hold it all together.
[/ATTACH][/ATTACH]
Now install the oil pump wear sleeve/the CLIP that fails into the case half if needed. Clean the case half mating surfaces, and apply a bead of sealant GM P/N 12345739 SPARINGLY!
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Make sure the alignment dowels are in the case half, and install the rear case half, make sure the oil pump housing is located in the proper location, the oil pump pickup tube will ensure this is in the right place. You will need the snapring pliers again, and spread the snapring in the case half while you pry on the bearing through the speed sensor hole, and get the ring in the bearing groove, and align the dowels and mate the two surfaces together.
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Install the case half bolts and torque them to 28 ft lbs. Remember this case is Magnesium, so do not apply to much force to any prying.
Reinstall the speed sensor and torque to 11 ft. lbs.
I used a dab of RTV and applied it to the rubber oval plug and reinstalled it.
Now all you have to do is reinstall it into the truck, I used a motorcycle lift, since I was doing this by myself, 2 people will make it EASIER!
Reconnect all the plugs, and don't forget the vent hose on top, now is the time to service the case with the DEX III Trans fluid or suitable substitute, do not service untill it is in the truck, or you will wear half of the fluid like I did while you are fumbling the case around while installing it.
I removed the steel band clamp that holds the rubber boot on the front drive shaft, If I had it to do again, I would just remove the drive shaft at the Differential and leave it with the transfer case. But since I removed the clamp, I used a GOOD quality heavy duty zip tie and installed it where the clamp was. The U-joint straps are torqued to 30 ft lbs or like I did it, good"n"tight.
I know the pictures are out of place, I have tried to do my best to put them in place, but they just would not go. So just make your self familiar with the process and have a go at it.
Please do not give me to much grief, I tried to do my best with what little computer knowledge I have to put this together. I want to thank a few members on here for thier help.
Lee Hill aka Airborne thanks for the actual pictures, they were a big help, especially since I did not take any, and also a Thanks to Joe Marlowe aka VB Dually for the crash course in computers so I could get this posted on the forum
Transfer case pump upgrade install as I did it.
I am going to be alittle generic about the Jacking and securing the vehicle, and some other steps, you should be able to do that if you are going to attempt theis pump upgrade. I have been struggleing with cut and paste of pictures to include with this instruction, so if need be I will include the disassembly proceedure, and reassembly proceedures along with the Transfer case inspection instructions, so use as needed. NOW LET'S GET STARTED!
1. Find a level surface, and jack and secure the vehicle, I used jack stands in my driveway, so you do not need a lift to do this.
2. Using a 11 mm wrench, remove the bolts that hold the U-joints in the the reaer end and the front end. Have some tape on hand to tape the u-joint so the cups do not fall off. After you remove the bolts, cut the band clamp on the rubber boot on the front driveshaft where it goes into the transfer case. Remove the driveshafts by sliding them out. I reinstalled the bolts loosly in the U-joint area so they would not get lost.
3. Drain the transfer case. I say to do this or you may end up wearing some of the fluid when you fumble the case around trying to get it out.
4. Locate and disconnect ALL of the electrical plugs that go into the transfer case. The sppeed sensor ion the tailshaft, and the encoder motor. Also trace the wires and locate where they are held out of the way by brackets, and make sure the wires are disconnected from the brackets as needed if the brackets are attached to the transfer case. I pushed the wires aside on the drivers side up on the frame.
5. Find you a good piece of wood or something that will cover almost the entire area of the transmission pan, you will be jacking on this area, so be careful and do not get carried away when jacking. Now jack a floor jack up to the transmission pan with the wood between the jack and the pan, do not put to much pressure on it, the mount is still attached. Get used to that jack being there, it will be there till cross member is back in place.
6. Remove the nuts that attach the transmission mount to the cross member, and jack the jack that is under the transmission pan untill you see the transmission move and is off of the cross member.
7. Remove the bolts that hold the cross member in the frame, and remove the cross member out of the way. Now remember the transmission is resting on the jack and the piece of wood that is under the transmission pan.
8. Now lower the jack SLOWLY until the transfer case is restin on the torsion bar cross member, this will make it easier to get to the top nuts that hold the t-case on the tranny. Now is a good time to find the VENT line that is on top of the t-case, and disconnect it from the plastic elbow, be careful, it is plastic, and can break.
9. There are 6 nuts on studs that hold the transfer case on the tailshaft of the transmission. With the transfer case resting on the torsionbar cross member remove the top 3 nuts using a open end wrench, you may be avble to use a socket, but I did it with a openend wrench.
10. Now jack the jack up until the t-case looks to be about to touch the bottom of the truck, and lock it down. Now remove the bottom 3 nuts off of the studs, now the transfer case is being held in place by gravity resting on the studs.
11. Now if you are strong enough, or have some specisl jack, get under it and slide it to the rear and off of the splines in the transmission shaft, and it will rest on the torsionbar cross member, BE CAREFUL, it is still unsteady untill you get it on the ground. I would assume this to weigh about 75 lbs, more or less, I did not weigh it.
12. Wrestle the case out from under the truck, I lowered it down by Armstrong, onto a creeper, then wheeled it out from under the truck. Now we are ready to get to the meat and potatoes of what we are out to achieve.
13. Find you a good working surface, I used a piece of wood on my tailgate, using deadblow hammers as chocks to steady it in whatever position I wanted. Now time to follow the transfer case disassembly proceedures, I only used the steps I needed, I did not remove the encoder motor or other parts, I only removed what was needed. So step 14 will be the instructions for disassembly of the transfer case, and then I will lay out what I did.
Remove the rubber plug on the transfer case tailshaft housing, and remove the speed sensor that is threaded into the tailshaft housing.
View attachment 35120
View attachment 35121
Now remove all of the case bolts, BE SURE TO MARK WHERE THE BRACKETS GO that are held on with some of the case half bolts.
View attachment 35123
Now with a pair of flat tipped snap ring pliers that will expand the ring, insert the pliers through the oval hole in the tailshaft housing that the rubber plug was blocking, and expand the snapring that is in there, this may be alittle difficult, but work with it, and pry on the reluctor wheel through the speed sensor hole with a screwdriver, to pry the case halfs apart and get the snapring to release the rear case half.
[/ATTACH][/ATTACH][/ATTACH]
When you get the case halfs apart, remove the snapring holding the bearing and reluctor wheel on the tailshaft, and remove the bearing, and reluctor wheel.
[/ATTACH][/ATTACH]
Remove the pump housing assembly, you will have to pull the oil pump pickup tube out of the housing, it is only held in place by a O-ring. Remove the Torx Screws T-15 holding the pump housing together, they are not very tight, and then separate the housing, this is a gerator type pump, sothere is not but 2 parts inside the housing, make sure to reassemble the new pump housing the same way you disassemble it.
[/ATTACH]
Now is the time to clean the inside of the transfer case, if it does not look clean, I used a can of degreaser and hosed down the inside of the transfer case and rinsed with the old garden hose. Used compressed air and blew out the excess water, and then removed the oil pump pick up and cleaned it and made sure there were no obstructions, and removed the magnet and cleaned it as well. I then reassembled everything in a reverse order, I spoke with Eric at Merchant Automotive about torque on the torx-15 screws, and we both agree that just get them good and snug/tight using BLUE locktite.
[/ATTACH]
Now reinstall the pump housing onto the tailshaft, followed by the reluctor wheel, the step on the reluctor wheel goes toward the pump housing. Then install the bearing, the groove is to face the end of the shaft, or up if you have the case pointing up. Install the snap ring into the groove to hold it all together.
[/ATTACH][/ATTACH]
Now install the oil pump wear sleeve/the CLIP that fails into the case half if needed. Clean the case half mating surfaces, and apply a bead of sealant GM P/N 12345739 SPARINGLY!
Make sure the alignment dowels are in the case half, and install the rear case half, make sure the oil pump housing is located in the proper location, the oil pump pickup tube will ensure this is in the right place. You will need the snapring pliers again, and spread the snapring in the case half while you pry on the bearing through the speed sensor hole, and get the ring in the bearing groove, and align the dowels and mate the two surfaces together.
Install the case half bolts and torque them to 28 ft lbs. Remember this case is Magnesium, so do not apply to much force to any prying.
Reinstall the speed sensor and torque to 11 ft. lbs.
I used a dab of RTV and applied it to the rubber oval plug and reinstalled it.
Now all you have to do is reinstall it into the truck, I used a motorcycle lift, since I was doing this by myself, 2 people will make it EASIER!
Reconnect all the plugs, and don't forget the vent hose on top, now is the time to service the case with the DEX III Trans fluid or suitable substitute, do not service untill it is in the truck, or you will wear half of the fluid like I did while you are fumbling the case around while installing it.
I removed the steel band clamp that holds the rubber boot on the front drive shaft, If I had it to do again, I would just remove the drive shaft at the Differential and leave it with the transfer case. But since I removed the clamp, I used a GOOD quality heavy duty zip tie and installed it where the clamp was. The U-joint straps are torqued to 30 ft lbs or like I did it, good"n"tight.
I know the pictures are out of place, I have tried to do my best to put them in place, but they just would not go. So just make your self familiar with the process and have a go at it.
Please do not give me to much grief, I tried to do my best with what little computer knowledge I have to put this together. I want to thank a few members on here for thier help.
Lee Hill aka Airborne thanks for the actual pictures, they were a big help, especially since I did not take any, and also a Thanks to Joe Marlowe aka VB Dually for the crash course in computers so I could get this posted on the forum
