8.3L Cummins Transplant

Front end is done, and the truck is currently driveable. Rails, cross members, etc are ready to be painted. Hoping to graft the frame rails on to convert it to a tandem axle next week.
It got lowered 4.5” up front, and will be 4” lower in the rear when done.
All new brakes, drums, bearings, seals, hubs stripped and painted, blah, blah, blah.
It somehow turned into more of a project than I anticipated!
 
Last edited:
I don't think I've seen a daycab freight shaker local here before. Good looking truck, I'm not a trucker, so its ok I like freightliners, ha.
 
I don't think I've seen a daycab freight shaker local here before. Good looking truck, I'm not a trucker, so its ok I like freightliners, ha.

Thanks!
It came from California, got “too old” to license out there. I bought it from the original owner.
I’m not particularly a Freightliner fan, but it had the drivetrain I wanted (475 hp C15 Cat, 13 speed), it had the correct number of stacks, breathers, battery boxes, had all those items in the correct locations, and it was in my budget, so.....
 
Last edited:
I put a bunch of miles on a 1998 Century, Detroit and a 13spd. It was registered as a "RV". Was a good truck for us over 250k miles. Just looked like **** with that slant nose.
 
I put a bunch of miles on a 1998 Century, Detroit and a 13spd. It was registered as a "RV". Was a good truck for us over 250k miles. Just looked like **** with that slant nose.

I hear ya on the slope nose look.
I think we derailed Jory’s thread a bit......sorry!
 
Supposedly leak free, probably be all he does for another two years!

Sent from my SM-G960U using Tapatalk
 
I am still interested. Done anything?

Why, yes....yes I have. It's a fiasco but it finally ended last night. :snoop:

So...….it started when I went to move the Chelsea PTO housing and the Vickers Vane pump from the FS-5005 onto the FS-5106 that I got from Signature600. The gear on the PTO housing wouldn't match the 5106 PTO gear. I took them both as separate units to Blumenthal Heavy Duty in OKC Dec 2015. I told them "I need this to go on there and new seals put in everything. I don't want to build a new truck and have it leak."

From the day I got it back, installed it into the truck, and filled it with synchromesh fluid...the mofo has leaked out on the PTO housing. Fast forward to a few months ago when I got it running. I called Blumenthals and they said sure, bring it back, we will fix the leaks. I also explained that it doesn't pump now and I have no fluid pressure. They said they'd take a look at everything.

A week ago last Friday, I go to pick it up and they have fixed all the leaks, put new seals in everything, replaced the PTO shaft and a filler plate yada yada yada. I paid for all the parts and they covered all the labor since they didn't seal it up the first time like the work order showed. Great folks, no issues with them, everything was dandy and fine. We discussed the fact that it still didn't pump and I said I'd dig into it since I didn't want to pay the for labor to chase it down.

Fast forward to night before last. The wife and I spend a few hours trying to figure out why there wasn't any pressure. Then yesterday after work, I had her look under the truck while I bumped the PTO after taking the pump back off again. She told me the gear was rotating CW. Now, this is the first time I had checked rotation because I was told "the two transmissions both have the same PTO rotation." If the pump worked on the old one...why the hell wouldn't it work on the newer one, right? Wrong. The pump was set up for CCW rotation. So after I took the input housing off, reversed the plates and rotor in the cartridge assy, and put it all back together.....we have hydraulic power!!!! It was a long, drawn-out, stupid deal....but I did learn how to reverse a vane pump and lots of other junk so it wasn't a total waste of time....even though it should have been set correctly the first time it was assembled. :D

I am having a few air brake issues, though. I've been in touch with Haldex trying to figure it all out. Sometimes the dryer purge valve will mysteriously open and start bleeding the wet tank. I'm still trying to figure out this saga.

I really need to do exhaust now that I can put the dump bed back on. I needed hydraulics to raise and lower the bed. The stack needs to be set so it doesn't interfere with the bed so it needs to be on the truck....but I need to raise it up and down to run the pipe and make brackets. I need an HX-40 housing clamp and fitting and some pipe and elbows.

So....it needs to be air brakes then exhaust. After that I should be able to move on to the hood stretch.

And I found out the gears in the rear end are 4.88 on the high side. Looks like 60 mph is going to be my max according to the road ranger calculator. Might need to lower the ratio in the next year or two. That's gonna suck on the highway.

O, and I still need to order a tachometer sensor. I need to get the tach on the dash working also.

attachment.php
 

Attachments

  • Ground Speed.JPG
    Ground Speed.JPG
    57.2 KB · Views: 0
Last edited:
Gear sets available are 4:33, 4:11, and 3:70.

Advice? I sure don't think the truck needs to do 78 mph. I'm thinking 4:11. Most work will be done with it at low speed. Seldom highway runs. What should I expect to run this motor at for longevity on the highway, Jeff, 23-2400? I don't have a tach yet so I'm not sure where it is gonna want to be. It does have a two speed in it so maybe the 3:70's wouldn't be a bad choice either...thought?
 
Gear sets available are 4:33, 4:11, and 3:70.

Advice? I sure don't think the truck needs to do 78 mph. I'm thinking 4:11. Most work will be done with it at low speed. Seldom highway runs. What should I expect to run this motor at for longevity on the highway, Jeff, 23-2400? I don't have a tach yet so I'm not sure where it is gonna want to be. It does have a two speed in it so maybe the 3:70's wouldn't be a bad choice either...thought?


I don't think it will be worth the headache to change the gear ratio, put a gov spring kit on it and rev it. :)
 
Don't rev an 8.3 over about 2800RPM for an length of time. Valve train isn't tough enough.

However, we run them at 2400RPM in combines for thousands of hours with no issues.

Chris
 

Thanks for the update.
The engine will be happy under 2200 RPM. Your sweet spot should be closer 1800 rpm.
2300-2400 at highway speed is not ideal, but I don't know how much highway time you'll require of old Jimmy. I do know that you live on flat land pretty much.
I don't want to read back, and I can't remember the transmission model.
Could be a two speed rear-end will be the answer.
 
Gear sets available are 4:33, 4:11, and 3:70.

Advice? I sure don't think the truck needs to do 78 mph. I'm thinking 4:11. Most work will be done with it at low speed. Seldom highway runs. What should I expect to run this motor at for longevity on the highway, Jeff, 23-2400? I don't have a tach yet so I'm not sure where it is gonna want to be. It does have a two speed in it so maybe the 3:70's wouldn't be a bad choice either...thought?

Definitely 3.70’s with that 2 speed rearend. I’ve never seen that type of truck with too high of a low gear, but I’ve seen plenty that had too low of a high gear.
2,200 rpm in direct with 3.70’s would give you 70.5 mph.
 
Last edited:
Appreciate all the info. I am a FIRM believer that slower traffic is more of a hazard than fast traffic. The speed limit on the two lane highway past the house is 65mph. I want to be able to drive it at a min of 65 and not be wrapping the engine above what is prudent. Looks like the 3.70 is the way to go. That would put me around 2000 rpm at 65mph and I'd still have a tad of overhead on rpms if I needed to pass someone for some crazy reason.

By this chart...it looks like 50 is about my max at 2000 rpm with 4.88s.

attachment.php
 

Attachments

  • Ground Speed 3.70.JPG
    Ground Speed 3.70.JPG
    70.3 KB · Views: 0
Last edited:
Gear sets available are 4:33, 4:11, and 3:70.

Advice? I sure don't think the truck needs to do 78 mph. I'm thinking 4:11. Most work will be done with it at low speed. Seldom highway runs. What should I expect to run this motor at for longevity on the highway, Jeff, 23-2400? I don't have a tach yet so I'm not sure where it is gonna want to be. It does have a two speed in it so maybe the 3:70's wouldn't be a bad choice either...thought?

stock gov starts pulling fuel about 1900-2000rpm
1600-1800 is nice cruise rpm
3.70 would be my choice

ISSO pro R13000 series, is what I used for tach

can get little more by getting taller tires... 42" tall tire is ~1950 @ 65mph with direct drive and 3.70 gears
 
Last edited:
I'm not sure how much of this pump is stock....it's a Mumau special build. And I hope to use the stock tack in the dash.....I ain't in ta Nigerian up my truck quite that much as to just screw another tach on the dash.
 
I'm not sure how much of this pump is stock....it's a Mumau special build. And I hope to use the stock tack in the dash.....I ain't in ta Nigerian up my truck quite that much as to just screw another tach on the dash.

I'm sure Jeff can post what he had out in it
 
Back
Top