Driveline question on LM7/4L60e swap

[69chevpu]

I am going to put a 5.3l lm7 and 4l60e tranny in my 67 C10 lwb. It currently has a 350 sbc with TH400 tranny.

What mounts can I use that will allow me to use the existing driveline without modifying it? If I can get by without changing the driveline that would be best.

I am planning to probably use an Entropy radiator with fans.

Will the ECE mounts keep the end of the tranny at the same point?

Any help will be appreciated.

[68GMCCustom]

with a 6.0L swap and turbo350 changed to a 200-4r... I had to have a new longer shaft made because I decided to locate the engine on sbc stands in the proper forward mounting holes to provide some room behind the motor for the coil and MSD box w/o having to cut the firewall. But had I chose to mount the motor with the 6cyl stands and motor mounts the sbc was originally on (using adapter plates)...the original shaft fit fine.

[tonypaul]

You also need to check to see if your 4l60e's yolk bolts into the back of the transmission. TH400/TH350's yolk slides in and out with the suspension. If yours bolts into the trans you will need to have your driveshaft modified with the correct piece to get it to work properly. I ended up getting a whole new driveshaft made, with all heavy duty parts to handle the 454 Vortec. I didnt want to rick using the old orginal driveshaft. It was like $345.00 for everything..

[69chevpu]

Tonypaul - Where did u get your driveline made? Where did parts come from?

68gmccustom - Thanks for the info.

[tonypaul]

Originally Posted by 69chevpu

Tonypaul - Where did u get your driveline made? Where did parts come from?

68gmccustom - Thanks for the info.

It was done at a local driveline shop here in Austin. They mostly do big rigs and heavy duty commercial trucks. I can get you contact info for you if you want but I figure shipping on something like this will be not worth with to you...

[69chevpu]

Tonypaul,
Thanks for the offer. I'll wait till the engine gets here in a week and then check out what I have to do. I'm sure I can find someone in this area to do the driveline.

Thanks, Mel

[tonypaul]

here is a pic of mine right before I put it in.

[78bronzechariot]

I did a lr4/4l60e (4.8 vortec) in my 67 c10 lwb. A local machine shop shortened and balanced my old driveshaft for $65. I used the adapter plates and factory stands mounted about midway between the factory v8 and 6 cyl locations gave me plenty of clearance around every part of the engine if I ever need to take anything back apart. I was originally concerned with this part of my build, but I just asked around at the parts stores that I frequent and they pointed me in the right direction. Getting everything mounted where it will be functional is more important than trying to work around the driveshaft. I used the adapter plates and factory stands mounted about midway between the factory v8 and 6 cyl locations gave me plenty of clearance around every part of the engine if I ever need to take anything back apart. Just my experience though.

[67C10BUB]

Originally Posted by 69chevpu

I am going to put a 5.3l lm7 and 4l60e tranny in my 67 C10 lwb. It currently has a 350 sbc with TH400 tranny.

What mounts can I use that will allow me to use the existing driveline without modifying it? If I can get by without changing the driveline that would be best.

I am planning to probably use an Entropy radiator with fans.

Will the ECE mounts keep the end of the tranny at the same point?

Any help will be appreciated.

I used the ECE motor mounts and trans mount and they lined up with the factory holes, but the drive shaft will have to be shortened. If you are going from a TH400 to a 4L60E you will also have to get a new slip yolk anyway for the trans. The TH400 is a 32 spline and the 4L60E is a 27 spline. I don't see any way to use the stock drive shaft.

[69chevpu]

Thanks for the info guys.

I am excited my Engine/Tranny/harness/pcm etc. just showed up today from Florida. Now I can actually get started.

I'll work more on getting the engine set in the way I want and then worry about the driveline. That will be down the road a bit.

Mel

[67C10BUB]

Be sure and read everyone's build threads. There is a lot of good info in there that could save you the trouble that we went through. Don't be shy about asking questions either. I'm sure we will all help if we can.

[69chevpu]

I've read every build thread at least once. What a treasure trove of info. I'm sure I wouldn't have taken this project on if I didn't know that you guys were there to bail me out.

I have more parts coming in.
Walbro 255 lph external fuel pump
Corvette filter/regulator
Doug Thorley headers
Corvette synchro for 4l60e
SA-1000 fuse/relay wiring

I still need to sort through what all -6AN fittings and hose I need. I've found a lot of info on this. Just need a quiet time to sit down and make out a list.

I am still deciding what engine mount adapter to go with and if I will need a different trans crossmember. Going from TH400 to 4L60e.

I am still deciding whether to just break down and get an Entropic(sp?) radiator.


Anyway, I sure appreciated all the info from you guys that have blazed the trail before me.

Mel