changing 8.1

[bill1wts]

Trying to get an 8.1 out of a 05 2500 hd. I am going to put another 8.1 in. This is hooked to an allison. Got the simple stuff unhooked. Need some help with some of the other...


I have a gas line tool but wont work on the f.i. line. Is this a specific chevy tool? Think mine is from auto zone and ive had it a few years.


Would it be better to leave all the power steering and coolant lines hooked up and just remove the pumps and brackets from the motor and put back on new motor.


Any tricks to getting it off the allison or will it slide off once i got all the bolts out?


I believe I will have to cut the nuts off the exhaust manifolds where the pipe attaches. I cant budge them.


The passenger side motor mount is kinda easy to get to but the drivers is not. Was thinking of unbolting the complete mount from the frame. Any suggestions?


Will I have to take the radiator out to pull the motor? Hope not but dont want to mess it up either.


Thanks for the help.


In case you are wondering. This is a work truck and the help drove it a week with no oil in it. Duh...thats why it said check oil. It spun a bearing and makes a lot of noise now.

[Mr. 250r]

Well i actually just helped my friend pull his out 2 weeks ago lol go figure... anyways the pull wasn't bad if you have the right stuff but we couldn't get the stupid fan off the front so we pulled it like that with the core support still on but here's what we did

Unbolted allison but left it in
Unplugged the entire wiring harness
Unbolted the exhaust
Unbolted motor mounts from bottom with extension and swivel socket which makes it really easy
pulled the radiator
left core support in but pulled the top of it off
Undid the power steering lines, left all brackets on *took alternator off to use a bolt to pull it*
left condenser in but unhooked it and pulled it out of the way

I even got some pics for ya =-p we had the option of our lift and a friends service truck to pull it which helps but im not sure what you do and don't have

Luckily you have a replacement because GM basically disowned this motor and the aftermarket does not exist except for dart and raylar heads maybe one intake and i think that's it

Now as far as the fuel lines go we used a plastic tool i think its somewhat universal, this is a returnless style motor i believe so we only had one line to remove then we unhooked the plastic tube that sits in front of the intake with the green cap on it it has a push fitting which is easy to figure out but the hard part is the one that sits right behind the motor and above the tranny

[bill1wts]

i have come to the conclusion it is beyond my mechanical ability. I will never get that thing out. im gonna put it back together and sell it as is and do something else. i take one step forward and five back with this project. when i get done ill have 5000 into a truck with 180000 miles on it and a used motor.

the windshield is cracked - the heat and a/c only work part time, speedo doesnt work, and the seats are tore up just cant justify putting this much money and time in it.

[truckdude239]

i hate that your having problems but i want to wish you the best of luck anyway we are always here to answer any questions you may have

[bill1wts]

I got over my hour of frustration, I am back at it. I will get the thing out somehow. I may have the whole truck in pcs before its over. Not sure i will get it back together. its no good the way it is so guess i cant hurt it.

working on getting tranny bolts out and the exhaust bolts. i cant budge the exhaust bolts so i am going to attemp to cut the nuts with a dremel.

cant get the fan off - going to see if the parts store will let me borrow the tool but dont think it is much better than the setup i have.

i will keep you all posted and hopefully my struggles will provide you all with some chuckles if nothing else.

[bill1wts]

I live about 5 minutes from a federated auto parts. They know me well. Let me borrow a clutch fan remover and power steering pump pulley puller. Got all that out of the way. starter is off. bell housing cover off.

dont know where the inspection cover is on the allison. taking a short break then back at it.

[bill1wts]

So i mark the tc and the drive plate and remove bolts.

when i put the new motor back in should i put the drive plate off original motor on new motor and line it up?

not sure ... this is my 1st experience with auto trans all my other projcts have been standard trans.

[bill1wts]

how and where do you hook vise grips to keep tc in trans?

[truckdude239]

the torque conveter shoudl stay in teh trans with out any help if its sitting kind of level, i've never line up the torque conveter and flywheel when putting one back together never hurt anything yet.

[truckdude239]

you said the speedo doesn;t work either is the neddle stuck at some point or just doesn;t read? the reason i ask is that the cluster are bad about teh steeper motors going out i replace the clusters all the time at work i buy them from dorman products though my loacl advance auto parts, they come preprogramed with vin and mileage takes about 5 mins to install

Heres the dorman list or reman clusters

http://dormanproducts.com/gsearch.as...&type=parttype


its a how to replace the stepper motors your self

http://67-72chevytrucks.com/vboard/s...d.php?t=511327

[bill1wts]

i got seven bolts out of bellhousing to motor ... how many are there everything else unhooked but i cant get it to pop. done for tonight, im beat.

i guess its the stepper on the speedo i have researched it before. i have a garmin mounted to the dash that is my speedo. it hasnt worked for a cpl years. thats the least of my worries right now. i have been told the heat/ac deal is an actuator.

im so close to having it out ... grrr

[bill1wts]

so i got the motors swapped - an '01 in and '05 out. I had to change everything but the block and heads. All the electrical connectors were different and the intake on the 01 had two gas lines the 05 has one. etc egr on 01 diff from 05,....anyways this is where im at ... i changed the timing covers because the 01 has a thinner cover and the cam position sensor is shorter and the connector is different. Put the 05 timing cover on - new cps, new crank position sensor (again connectors were diff). It starts and runs sounds great but cel comes on. code 0342 - cam position sensor - put another new one in it and still throws code ... any ideas? sometimes it starts hard but runs good once going. not sure i have ability to test circuits. all i have is an ohm meter. is the 01 cam different from the 05? any help greatly appreciated - thsi project has taken awhile but we had a death in the family during it and a few other ordeals along the way. hate to take it to dealer but may have to now.