Home > Howto > Transmission Removal
home database faq contact links how to SyTy Desktop Wallpapers

    Transmission Removal

Part I

Here’s what I found out while going through my trials and tribulations with my Ty’s tranny. I had to pull mine 3 times in a week because of different problems I will tell you about later so you don’t make the same mistakes I did. Wish somebody would have told me. I got to where I could pull the tranny in 1 hour and 15 or 20 minutes. Wish I couldn’t brag about that.

Use some kind of small storage containers(like styrofoam coffee cups) and mark what your screws are for when you place them in individual containers SO YOU DON’T LOOSE THEM


Disconnect the TV cable from the throttle body and bracket. This way you don’t tear up your cable when you lower the tranny slightly later.

Get the truck up high as you can. Autozone has an SUV jack that can go 21”. This way you don’t have to crib anything up. Just get some heavy duty 6 ton jack stands, they go much higher than the 4 ton. Get front and rear both off the ground and the truck even as possible. Make sure it is secure and stable. Use cribbing if you have to in order to get the truck STABLE. No one wants to hear of someone dropping a truck on themselves because they weren’t careful.

Take off the tranny pan and drain the fluid into a catch pan. I used a Tupperware clear storage container(like you get at Walmart). It is 5 inches deep, 18 inches wide and 30 inches long. Holds lots of fluid. Put the pan back on.

Use some paint and mark the respective points on the rear shaft’s universal to the yoke on the rear differential. Take the four 7/16” bolts that hold the rear driveshaft to the rear differential. Spray with PB blast. Take a small pry bar and pop it out. Hold onto it while you pop it out so it doesn’t fall.

If you have a tranny adaptor, put it on the jack and jack it up until you just make contact with the tranny pan plus a little extra pressure. Just a little.

Use PB Blast whenever possible.
I remove the trans cross member first after the rear driveshaft. Use a 15mm socket and remove the two mount bolts on the bottom of the shelf for the mount. Put another jack(I have two)under the cross member. Just put it up until it makes contact.
Use a 15mm deep well socket with a 3” extension and a 15mm wrench to back up the bolts and nuts when you remove them from the cross member where it meets the frame. Do the driver’s side first since it will hold itself up. Then do the passenger side. Lower it. Check your “shelf” for the tranny mount. The weld on the passenger side of mine was cracked. Look closely. I could just see daylight through mine. It was only $13 to have the whole thing professionally rewelded. They did triple welds on both sides of all welds(even redid the ones that weren’t broken). They guy told me GM didn’t do the best job he had seen. GM’s weld didn’t even penetrate the steel.

Now for the mount bolts that hold the mount to the transfer case adaptor. Use a closed end 15mm wrench. Get on the bolt head and work it slowly with PB Blast and the wrench. Once it breaks loose. Work it back and forth. And then take it out. Take your time on these. Don’t use a socket on them. It will catch at a slight angle due to the tranny mount interference and as soon as the bolt breaks loose you will snap the head off or crack the adaptor. The adaptor is $64. HuRyde has the part number.

Now take off your front driveshaft. I use a 3/8” 12 point closed end wrench on the front and a 7/16” close end 12point on the rear. The way my propshaft is made, torx type socket that is made for the bolts won’t clear the double cardan in the rear and catch at an angle. Something here that helps: take out the cotter pin and slip the shift cable off of the manual lever on the tranny. Hang the cable back out of your way. Now you can shift it between park and neutral while you are working on the prop without having to get out from under the truck.

You can take the TC inspection cover off now. USE THE PROPER TORX BIT. I can’t stress that enough. The previous owner tried to use an allen wrench. It only caused headache for me.

Use a big flat head screwdriver to get under the mounting pads of the TC and turn it until you can get a 15mm closed wrench on the bolts. Use the screwdriver to back up the TC so it doesn’t turn while you take the bolts out. There are 3 of them. I took a 15mm close end wrench and cut the open end off. I could then use a small 3/4” copper pipe and break them loose. DON’T PULL TOWARD YOUR FACE. I have an ER visit for my chin and a nasty infection to show for it. Duh!!! Don’t turn the TC too fast or the compression from the engine will turn it back the other way. And the screwdriver can get you. Uh, yeah These 3 bolts have orange locktite on them. You can now slide the TC toward the tranny ever so slightly.

On to the transfer case. With the front prop and tranny crossmember out, you can get to the transfer case to transmission bellhousing brace easily. Use a shallow 14mm socket and your wobble extensions connected together so you get a slight arch to clear the tranny pan. Break it loose and get it out. The bolt is very long. You will have to leave it in the the brace sleeve but loose from the bellhousing. Now you can use a 15mm shallow socket on the rear bolts that hold the brace to the bracket on the transfer case. You take out the two that face up and down. The other two that actually hold the brace bracket to the transfer case you leave alone.
Wiggle the brace out.

Use a shallow 10mm to take the screw out of the little bracket on top of the transfer case that holds the fuel lines to the transfer case. Disconnect the electrical connector for the speedo out of the side of the transfer case. Also use a pair of small pliers and squeeze the spring loaded clamp on the vent for the transfer case. Slide the clamp forward and carefully pull the rubber hose off of the white plastic vent.

Now the hard part use a 15mm deep and shallow with extensions in different combinations to get the 5 bolts out that hold the transfer case to the tranny. Leave the bottom one in. That way the transfer case doesn’t spin down on you. IT IS HEAVY. I didn’t drain mine. 1 and 1/2 quarts of tranny fluid can’t weight that much. If this is the first time you have taken it out, it won’t spin. It probably won’t move. Back out the bottom bolt but leave a few threads of the bolt in the transfer case so transfer case can move but not spin. Now, grab ahold of the tail end of the transfer case where the rear driveshaft went into the transfer case. Work it up and down while pulling or pushing toward the rear. Some fluid that was trapped in the rear of the adaptor where the governor is will pour out as the transfer case moves toward the rear of the truck, use a small pan or some towels to catch it. It is very heavy. Have someone help you get it out. Really. Unless you are in a hurry like I was myself. There is a gasket between the transfer case and the tranny adaptor. I made mine from 1/16” inch gasket material like you get at any auto parts store using what was left of the stocker so I don’t know the part number. Don’t use form a gasket or anything like that. It can contaminate your tranny fluid or jamb stuff up, like a governor that is right beside it and is very important to shifts as well as some other valves.

Part II

You should be down to the tranny by now.

There is a plug for the TCC. Pop it out like you do any other weather pack connector. Pull out on the tabs while pushing up.

There is a rusty 8mm screw just over top of that that holds everything to the side of the tranny. Take it out.

There are 6 bolts in the bellhousing. One of them is out because the transfer case brace went through it on the bottom driver’s side.

The Next one that comes out is the TOP one on the passenger side. It is a 14mm and does not have a flange on it since it has the brace for the dipstick tube acting as a washer. Use a shallow 14mm, your wobble extensions and several extensions until you can get square on the bolt head. You do NOT want to strip these off. I used a halogen lamp placed facing up at an angle on the passenger side so this area would be illuminated. I was on my right side, legs sticking out the driver’s side so I could see it. Get it out. Goes back in easier than you would think. It is a bear to get out. GM used a white lock tight like stuff on it. You HAVE to take this one out first or your socket won’t fit squarely on the top nut I’ll talk about next. The vent tube for the transfer case is held up there also. Pull it out and lay it aside. When you put the vent tube back on, do like the factory did with everything else and run it zip tied to the fuel lines and run it up the driver’s side. Don’t know why they didn’t do this the first time. It makes R&R so much easier. After you get the bolt out, get up on a small step stool and use a pair of needle nose pliers and grab ahold of the dipstick tube and pull up, and slightly forward. It will be tough but will pop out of the tranny. The seal will come with it. That’s OK. You’ll have to replace it anyway. Turn it so it just clears some of the wiring and let it hang in there. You don’t have to pull it all the way out.

I now went to the two lower nuts you can get your hand on on the passenger side where the downpipe bracket is. Use PB Blast again on the 15mm bolt that holds the bracket to the downpipe. Use a shallow socket and wobble extensions arranged again.

Now the 14mm nuts that are over the bracket. The bottom one is cake. Shallow 14mm with wobble extensions. The top one had me scratching my head. There is a pinch weld on the body that would not let a deep well 14mm on it. The stud stuck out too far for a shallow socket. I had an extra 14mm deep. I took a dremel and cut 1/2” off of it. Cleared the pinch weld and seated squarely on the nut despite the stud. Take it off.

Now the damn bracket for the downpipe. Get your hand up in there(it will fit)and work the bracket until only a couple of threads hold it on there. It will not just come off. Once you get it there, Take a long, sturdy flat head screwdriver, get under the bottom hole on the brace and pop it off the stud. It won’t hurt the threads of the stud. The threads are a stronger steel than the brace. It may band a little, that’s OK. A regular deep well 14mm socket will get both studs out now.

The top one on the driver’s side is next. Work your wobbles and move your light so you can see it. Use a shallow 14mm on it. It is a little tougher because of the fuel lines but get square on it and take it out. Have a magnetic extension for grabbing the socket or the bolt in case they fall out up there. They will more than likely.

The last one uses just a closed end 14mm wrench. Once it is loose, you can get your hand up in there and get it out the rest of the way.

Almost there.

If you have never had your tranny out before, it will be bonded to the engine of sorts. Corrosion between the cast iron block and the aluminum bell housing.

I used a very thin flat head screwdriver with a long shaft on it. I stuck it at the joint and tapped on it with a hammer. I worked both sides evenly. Once I got them as far as the thin screwdriver could get them, I used a cold chisel I had that was about 1/2” thick. I placed it at the now open slot and tapped it in until the trans cleared the two alignment dowels on the engine. Thank God GM used these!! Use some scotchbrite and clean the mounting surface up and wipe off with some of the PB Blast or WD-40 to get rid of some of the corrosion.

DON’T FORGET TO DISCONNECT THE TV CABLE AT THE THROTTLE BODY!!!!! Now that the trans is separated from the engine, drop it down slightly. Just enough to where you can get the 10mm socket on the small bolt on the passenger side top of the plate the pan bolts to. This is the TV cable housing where it enters the tranny. After the bolt is out, push up and slightly toward the front of the truck at an angle. It is tough but it will slide out. You can push up on the housing and see where the cable slides over the little bracket for the TV line rise valve’s spring loaded bracket. Just wiggle it a little and it will slide off.

You can now see the tranny lines. Drop it down just a little more so you get your arms up in there. I can’t remember for sure but I think the brass fitting at the tranny is a 5/8”. The part that is tough to get loose is the 13mm for the tranny lines. I used line wrenches and PB Blast but it still rounded the corners off of the bottom one. The top one comes out first and was easy on mine. The bottom one I had to use a 6” small pipe wrench I had and careful worked it loose. No real damage. I stopped as soon as I saw the rounding off crap going on and went for the pipe wrench so as not to render the nut unusable.

Pop the line out of the hole in the fitting and the tranny is free. Lower it down. I had to slide mine off of the jack and onto the floor onto some waiting cardboard. It cleared the frame by a 1/2” or so. If yours isn’t that high, slide the TC off(lots of fluid in there too, have towels ready)and tip the rear up. This will angle the front down enough to get it out from under there.

Get ready for the rebuild.

Have two 2x4s about a foot long to stand the trans up on. Place these inside the same container that you drained the fluid into before. Hopefully you have emptied it by now so it is completely empty. Lay the 2x4’s on the wide flats in there and set the transmission on the tail end. You need this clearance because the output shaft sticks out 3/8” to a 1/2”. Let it sit for the rest of the afternoon if you have time. Fluid will run and run and run. Let it bleed. You’ll be amazed how much is left in there.

I laid the stock TC snout down in a pan and let it drain. The stock TC holds almost 3 quarts. Unbelievable.

There are books written on the rest. ATSG, Haynes, and Helms are all good cross references.
I tried to include everything. If I left a part out, let me know. I’ll write a little thing on putting it back in that will help it go a little quicker also.

Wish someone would have written this crap for me
George (mailto:[email protected])
Blake from syty.net forums.