Oshkosh MK48 Parts and Info

[paradeduty]

Thought it might be time to start a thread to possibly "group together" any helpful information and parts availability for these trucks due to their uniqueness.

 

[paradeduty]

To start the ball rolling.......I finally got a chance to get to a real fasteners supplier to get some additional "drive flange" bolts. These are the ones (8 total) that hold together the two round mating flanges for the rear driveshaft between the MK48 Front Power Unit and whatever Rear Body Unit you happen to have or are in the process of "hitching up". Quite a few folks may be missing a couple of these if their truck was part of the Jacksonville, Florida, auctions as I believe that not many of the bolts were available under this "unique" recovery situation.

Anyways, brought a sample for them and not a big mystery bolt, but every supplier may not stock them. So it might be helpful and less agravation for some to be able to know the bolt size and call ahead for availability.

These bolts should be 3/8 inch x 1-1/2 inch long Hex Cap Bolts, 24 Threads per inch, Grade 8.

The nuts for these bolts should also be 24 TPI and Grade 8, as well as being the "self-locking" style.

By the way, these cost me just under $12.00 for 10 (a couple spares!), so you shouldn't have to pay a fortune.

Hope this helps, Dave.

 

[73m819]

To start the ball rolling.......I finally got a chance to get to a real fasteners supplier to get some additional "drive flange" bolts. These are the ones (8 total) that hold together the two round mating flanges for the rear driveshaft between the MK48 Front Power Unit and whatever Rear Body Unit you happen to have or are in the process of "hitching up". Quite a few folks may be missing a couple of these if their truck was part of the Jacksonville, Florida, auctions as I believe that not many of the bolts were available under this "unique" recovery situation.

Anyways, brought a sample for them and not a big mystery bolt, but every supplier may not stock them. So it might be helpful and less agravation for some to be able to know the bolt size and call ahead for availability.

These bolts should be 3/8 inch x 1-1/2 inch long Hex Cap Bolts, 24 Threads per inch, Grade 8.

The nuts for these bolts should also be 24 TPI and Grade 8, as well as being the "self-locking" style.

By the way, these cost me just under $12.00 for 10 (a couple spares!), so you shouldn't have to pay a fortune.

Hope this helps, Dave.

ALL The bolts we found (when they were there) were standard grade 8, the funny thing, ALL the NUTS were STANDARD grade 8 nuts with grade 8 LOCK WASHERS, I was surprised because ALL the driveline conection bolts I have ever seen are the SPECIAL DOWEL bolts along with the self-locking nuts.

 

[paradeduty]

Agreed, Ron.

While I was at the parts counter, I just handed the sales rep. the spare that was in my cab with a buggered thread and he came back with the self locking nuts. I wasn't sure if it was original, but on a driveline component spinning at some serious RPMs, I didn't think it was a bad idea at all! As I described it, the nuts "should be ......."! Not familiar with the "dowel bolts" of which you speak. Just out of curiosity, what is the difference?

Dave.

 

[73m819]

Agreed, Ron.

While I was at the parts counter, I just handed the sales rep. the spare that was in my cab with a buggered thread and he came back with the self locking nuts. I wasn't sure if it was original, but on a driveline component spinning at some serious RPMs, I didn't think it was a bad idea at all! As I described it, the nuts "should be ......."! Not familiar with the "dowel bolts" of which you speak. Just out of curiosity, what is the difference?

Dave.

DOWEL bolts have a longer UNthreaded area between the head and the start of the threads, they only have about 1 thread in the flange, the rest is unthreaded, makes for a stronger connection, look at a OE bolt out of a 5t connection, may be 1 1/2" bolt but less thread then a STANDARD 1 1/2" bolt, the unthreaded part is just a blond hair smaller then 3/8", a finger press would be right for a new bolt and flange.

I'll find the p/n for the 5t bolt, I got mine from one of the major venders----7376150

 

[Nonotagain]

I believe the trade name for the bolt you attempted describing is a shoulder bolt.
They are not designed to carry a high clamping load due to the reduced thread diameter.
High strength fasteners are constructed with a minimal number of threads, typically using rolled threads verses cut threads.
"Shoulder bolts are screws with an unthreaded shoulder that is larger in diameter than the threads. Also known as stripper bolts."

 

[73m819]

DOWEL bolts have a longer UNthreaded area between the head and the start of the threads, they only have about 1 thread in the flange, the rest is unthreaded, makes for a stronger connection, look at a OE bolt out of a 5t connection, may be 1 1/2" bolt but less thread then a STANDARD 1 1/2" bolt, the unthreaded part is just a blond hair smaller then 3/8", a finger press would be right for a new bolt and flange.

I'll find the p/n for the 5t bolt, I got mine from one of the major vendors----7376150

I believe the trade name for the bolt you attempted describing is a shoulder bolt.
They are not designed to carry a high clamping load due to the reduced thread diameter.
High strength fasteners are constructed with a minimal number of threads, typically using rolled threads verses cut threads.
"Shoulder bolts are screws with an unthreaded shoulder that is larger in diameter than the threads. Also known as stripper bolts."
View attachment 360787

The threads on the drive line connection are not reduced in size, still standard 3/8, just the shoulder is longer then a normal 1 1/2" 3/8 grade 8 bolt, the shoulder (shank) is just a blond hair under 3/8 so it is a snug fit in the flange.

Apparently the bolts (7376150) are a mil. spec. bolt, my bolt supplier had nothing in his catalog to match, I got mine from Sam Warner( SP ???), my nos bolts were black in color (in-pack black), the same color as what was OM,

The 48 drive-line connection flanges are the SAME as the 5t connection flanges, so it does NOT make sense that the bolts would be changed from mil. spec. bolts used on the 5t (7376150) to standard grade 8 that seems to be used on the 48s, a vehicle that is at least 3 times larger all the way around ( HP, TORQUE, WEIGHT, LOAD CAPACITY).

 

[TreadLite]

Any one parting out a motor or pieces? I'm looking for an exhaust 90 on the passenger side. It fits after the exhaust manifold and onto the pipe that goes up to the turbo. Needed ASAP. Thanks!

 

[theQ]

Hi yall, I broke the front drive shaft on my Mk48 anyone know where the best place to find a replacement?

TIA

 

[simp5782]

Hi yall, I broke the front drive shaft on my Mk48 anyone know where the best place to find a replacement?

TIA

Any Driveshaft shop can make you one. Nothing special about it