The Stovebolt Site Forums The Parking Lot Big Bolts Hey big bolt , help a small bolt

Hey big bolt brothers, I need some help! I have a 48 3/4 ton and am looking to buy a 59 261 engine (complete with bellhousing and transmission attached)out of a 59 2 ton truck. I have not see it in person but have looked at photo's. The crossmember's and mounting positions for the bellhousings look different between the trucks. I was hoping to just bolt the whole 261 setup in my 3/4 but I'm not sure if it will mount up the same. Can anyone shed any light on this? Thanks, Scott

In the 54 yr, GM changed the motor mounts and the cross member of trucks. Your tranny will still bolt on to the new bell, but the mounts won't work. If your engine is a 216 in your 48, then I dont think it will fit on a 261. I beleive that you will have to find a bell from 235. I"m not sure on this part but I do know the mounts changed.

You should be able to use your '48 bell housing to solve the rear mount problem.

Hopefully the '59 engine will have the lip for the front motor mount but probably won't have the holes for it. Take measurements from your old engine and lay out the holes on the lip. Drill them then square the holes with a file.

You'll also have to shorten the shaft on the 261 water pump and get a shorter pulley. There's plenty already posted about that so do a search.

One more thing. If you want to use your 6V starter, you'll have to use the '48 flywheel.

Sorry Cletis, didn't mean to ruffle any feathers, was just trying to get different perspectives--wasn't sure how often you big bolters venture out, I know this is the first time I have ever ventured into yall's sand lot. Thanks for the quick response! I want a 12v starter so if I understand you right, all I will really need to do is exchange bellhousings. One other question if you don't mind. The 261 is an open driveline transmission with the emergency brake on it. Do you forsee any problems here? and will I still have to use a carrier bearing or could I have a single driveshaft made (I am switching the rearend to an open driveline from a 64 chevy with 3:73 gears). Thanks, and by the way I like your web site! Scott

Sorry, I'm not familiar with the drive line on a '48 ¾-ton. I thought ¾-tons had open driveline. You seem to be suggesting it now has a closed shaft. Someone else best answer this one.

I would use the 4spd with the brake on it if mine. You will need the 48 bellhouse as noted to get the angled mounts there. The trans hangs off the bellhouse, no mounts for it. You will need the floor section from big truck as it is higher to clear trans, the 3spds won't work. Yes, you will need a mid-joint and two shafts. You will also need crossover to mount the joint on. Didn't your 3/4 have two piece and bearing? Should have I think. Lengths may change, and you may have to have one lengthened, probly front.