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Anyone regret doing a Cummins swap?

Took it off again and noticed it's hitting the lifting eye, probably because it's bent forward. I bent it back as best I could with it being under the firewall. It looks to have a hair gap now.
 
Drove this out of town for the first time. Took me to the Courthouse to succeed in getting a bs parking ticket thrown out. :usa:

Even calculated milage for fun. Probably not super accurate since I topped it way off out of my transfer tank last time, but whatever.
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Should be like double that, so I need to figure out what's wrong :homer::flipoff2:

Wish I had a tach to see what I was turning, but even 65mph felt kinda high rpm. Who knows though, haven't driven the truck in a while.

Either way, everything went good.
 
Doin' better then mine is, I haven't seen higher than 12 with mine. Although it doesn't leave the house without a trailer behind it and/or camper on it.
 
lucky bastards....with 4.88s I overrev the shit out of it. Its good for power, bad for mileage. 10 mpg empty (13k) 8mpg at 20-30k gross at 70 mph about 2500 rpm
 
06h3 said:
lucky bastards....with 4.88s I overrev the shit out of it. Its good for power, bad for mileage. 10 mpg empty (13k) 8mpg at 20-30k gross at 70 mph about 2500 rpm
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Still not bad for what you have.

What's your current plan to lower rpms? I think an Allison 6 speed would be pretty sweet.
 
Way behind the 8 ball on this one.

I did it on an '05 King Ranch 3fiddy. Short story...I got rid of it as well, not by choice. It burned basically to the ground just outside of Vegas. In 2014 so I've lost a few brain cells since then.

Anyways, I don't remember all the details anymore. 12v, upgraded turbo, governor springs for sure. I don't remember if I did injectors. I was able to plow with it for one season and this thing would move a mountain of snow at idle. Sucked on the high end, but low and mid it was amazing.

Was on the phone with the idiot insurance whatever while still on the side of the road. He wanted to send an adjuster to check if it was totaled. Emailed some pics...Oh, we don't have to bother with an adjuster.
 
YotaAtieToo said:
Still not bad for what you have.

What's your current plan to lower rpms? I think an Allison 6 speed would be pretty sweet.
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Depends on the day. :flipoff2:
1) Do nothing
2) Aux box
3) Allison swap (well documented)
4) wait till the new ZF 8AT comes out in the ram. See if the bell housing is SAE stuff. I am 98% sure it is according to their PDFs. If it is adapting it to a 7.3 wont be too difficult because there are SAE adapters. I am also pretty sure it uses the same computer as the 8HP70 stuff which has standalone stuff. Have an 8 speed that is bomb proof since that 8AT is designed to go behind anything up to 57k gross

ZF is the best thing that ever happened to Ram/Jeep/Dodge. They 8HP variants are behind everything and you hear of all the compliants about 8-10 speeds in GM and Ford and everyone shits on the ram 2500-3500 6 speeds but no one complains about 8HP behind JL's, Hellcats or Ram 1500s so I think the ZF If the way to go but were not there just yet.

So anyways, those 4 options cross my mind just depends on the day. I like to dream up tow rig stuff
 
TrailTamer said:
Did you thought the swap will change the rpm at same speed? :flipoff2:
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:laughing::flipoff2:

TrailTamer said:
most likely lol

be happy you have overdrive. My n4500 self-deleted its overdrive gear. :frown:
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Dodge with transmission problems? Wierd :flipoff2:

06h3 said:
Depends on the day. :flipoff2:
1) Do nothing
2) Aux box
3) Allison swap (well documented)
4) wait till the new ZF 8AT comes out in the ram. See if the bell housing is SAE stuff. I am 98% sure it is according to their PDFs. If it is adapting it to a 7.3 wont be too difficult because there are SAE adapters. I am also pretty sure it uses the same computer as the 8HP70 stuff which has standalone stuff. Have an 8 speed that is bomb proof since that 8AT is designed to go behind anything up to 57k gross
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I'd be surprised if they used sae bellhousings in a pickup, they're huge. When I looked at that with my 7.3, people said you'd have to completely change up pipes and turbo location.

Sounds like it would be cool, but a huge can of worms compared to the proven Allison. Not to mention trying to get you hands on a transmission that just came out.

06h3 said:
ZF is the best thing that ever happened to Ram/Jeep/Dodge. They 8HP variants are behind everything and you hear of all the compliants about 8-10 speeds in GM and Ford and everyone shits on the ram 2500-3500 6 speeds but no one complains about 8HP behind JL's, Hellcats or Ram 1500s so I think the ZF If the way to go but were not there just yet.

So anyways, those 4 options cross my mind just depends on the day. I like to dream up tow rig stuff
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What rpm is the motor turning on the highway? The Cummins motors like less cruising rpm than powerstrokes in my experience. Might be time to regear.
 
GLTHFJ60 said:
What rpm is the motor turning on the highway? The Cummins motors like less cruising rpm than powerstrokes in my experience. Might be time to regear.
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I don't know since I don't have the tack hooked up. According to the Gear calculator if I measure my actual rolling radius of the tires at like 14 1/2" :homer: in at 2k rpm at 65.

I already have 3.55s, so realistically, there is no where to go r&p wise.
 
YotaAtieToo said:
I don't know since I don't have the tack hooked up. According to the Gear calculator if I measure my actual rolling radius of the tires at like 14 1/2" :homer: in at 2k rpm at 65.

I already have 3.55s, so realistically, there is no where to go r&p wise.
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No, but you could up size the tires to get more effective gear out of it.

My truck gets best mileage between 1800 and 1900rpm on the highway going 70-80.

Edit: my truck meaning my 4bt swapped cruiser.
 
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Shame that there is no modern equivalent to 9.00-16 available for decent price. I'm a fan of 255\85R16 and 255\80R17 but even those are more than their wider counterparts. 35x10.50R16-R17 in an all terrain seems like it would sell decent but don't really see much.
 
350TacoZilla said:
Shame that there is no modern equivalent to 9.00-16 available for decent price. I'm a fan of 255\85R16 and 255\80R17 but even those are more than their wider counterparts. 35x10.50R16-R17 in an all terrain seems like it would sell decent but don't really see much.
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I run 35x10.50r17s on my 4runner and like them, but the wieght capacity sucks on skinny tires.

A 285/85r16 or 295/80r16 would probably be perfect.

I've even thought about doing a legit weld on beadlock like through trail ready, to widen them, but I'm still stuck with 16s.
 
350TacoZilla said:
Shame that there is no modern equivalent to 9.00-16 available for decent price. I'm a fan of 255\85R16 and 255\80R17 but even those are more than their wider counterparts. 35x10.50R16-R17 in an all terrain seems like it would sell decent but don't really see much.
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235/85/16 is my choice
 
Towed for the first time with the 12v.

Scaled it for funsies
Irrc it was

Fr: 4220
Rr: 5720
Tr: 10440

So right at 20k lbs (conex was empty) did OK. Haven't messed with the pump at all, seems pretty close to what the 7.3 was but in a much narrower window.

Definitely not even remotely the same ball game as the 6.7 with this exact load....... But it's also runs, so big advantage there :laughing:

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Fwiw, I didn't tie it down.... :flipoff2:
 
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So when I went to hook up to the trailer, it didn't shut off with the key. Got home and found this.

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Stupid cheap FSS kit:homer:

Easy fix

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But now the solenoid it's self won't hold, not sure if it didn't like being disconnected. Zip tied it up because I had to pick this up.

20241109_141139.jpg


It's been doing fine. It's definitely a much different experience driving. Similar power to the 7.3 over all, but the 7.3 was so linear where this is just a short burst at a lower rpm. If you just floor it you can kinda feel the tranmission being unhappy at lower rpms. Kinda have to roll into it to get the rpms up before you shift if that makes sense.
 
Need to adjust the length of the rod. Too short or long and it won't hold.
 
so take it loose, turn your key on, and push it in and see if it stays.
I've had to adjust mine a few times. take the two top mount bolts loose, and make sure its not sticking up above the mount with it turned on and not screwed down.
 
V30crewcab said:
so take it loose, turn your key on, and push it in and see if it stays.
I've had to adjust mine a few times. take the two top mount bolts loose, and make sure its not sticking up above the mount with it turned on and not screwed down.
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Good to know, I figured it was a once and done adjustment
 
06h3 said:
How’s the 5.9 towing?
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See a few posts up.

But it's doing good. The mini Ex is 13k lbs plus ~5k lb trailer and it wasn't too bad. I didn't pull any grades though.

It will pull a lot harder than the 7.3, but for such a short burst. 7.3 took a little more to get into the power, but there was so much rpm range it was somewhat easy to keep in the power.

But to be fair, the 7.3 had the stock shitty obs turbo, where the 12v at least has the he351. Plus I have a ton of room for more fuel.

Brakes still suck, kinda like the gearing, cummins swap didn't change it for some reason :laughing::homer:
 
Brakes can get better with modern axle brake stuff. Idk if you can put bigger calipers/rotors on or have to swap the axles entirely but I imagine there’s upgrades.
 
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