Dismiss Notice

Welcome To CK5!

Registering is free and easy! Hope to see you on the forums soon.

Score a FREE t-shirt and membership sticker when you sign up for a Premium Membership and choose the recurring plan.

Swaped a 400/203 out, put in a 350/203 Driveshafts?

Discussion in 'The Garage' started by Klink K5, Apr 20, 2003.

  1. Klink K5

    Klink K5 1/2 ton status

    Joined:
    Aug 3, 2002
    Posts:
    549
    Likes Received:
    0
    Location:
    Northwest Iowa
    All right, The 400 turbo burned up in the old 79 GMC 3/4 ton farm truck with a 10 bolt front axle. The set up I put in the truck was out of a 1976 chevy 3/4 ton with a dana 44 front axle. I got everyting bolted in there ok, but my question is, will the front driveshaft of the 76 f#%k up my transmission by the driveshaft being too short. Correct me if im wrong but I think (with out looking at both front axles) that the dana 44 pinion is shorter than the 10 bolt front axle. It looks like the front shaft is too long of the 76 to go into the 79. Am I correct? Any help would be appreciated! Thanks, Klink /forums/images/graemlins/truck.gif
     
  2. hoosierk3500

    hoosierk3500 Registered Member

    Joined:
    Jun 5, 2001
    Posts:
    44
    Likes Received:
    0
    Location:
    Huntington,Indiana
    I could very well be wrong but I think the reason your driveshaft seems too long is the th400 is longer than the th350.I'm sure someone willpost up and correct me if I'm wrong.Jason84k3500 /forums/images/graemlins/truck.gif85k2500 /forums/images/graemlins/burb.gif
     
  3. HarryH3

    HarryH3 1 ton status Author

    Joined:
    May 31, 2000
    Posts:
    10,384
    Likes Received:
    2
    Location:
    Georgetown, TX
    The Turbo 350 is a few inches shorter than a Turbo 400. I don't know if GM made up the difference using a different length adapter or not. I swapped from a 350/203 to a 400/205 and had to move the tranny crossmember several inches back. Using a driveshaft that is too short can result in the shaft pulling apart when the front suspension goes to full droop. /forums/images/graemlins/shocked.gif But worse yet is using a shaft that is too long. It can bottom out when the suspension gets compressed. This usually results in breaking either the transfer case or transmission as the shaft presses back against the transfer case. /forums/images/graemlins/eek.gif
     
  4. HarryH3

    HarryH3 1 ton status Author

    Joined:
    May 31, 2000
    Posts:
    10,384
    Likes Received:
    2
    Location:
    Georgetown, TX
    Here's another thought... Measure the distance between the yokes, using the centerline of where the J-joint caps will be as the measuring points. Then measure both the fully stretched and fully closed length of your front driveshaft, again using the centerline of where the J-joint caps will be as the measuring points. With that info, any driveline shop would be able to tell you if your driveshaft will work. If you don't have any local shops, drop a PM to Drivelineman. Jesse is the owner of www.highangledriveline.com and flat knows his stuff. He can tell ya if you need to mod the shaft that you have. /forums/images/graemlins/cool.gif
     

Share This Page