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Author Topic: Can we start a Cummins swap info/questions thread?  (Read 18250 times)

mdemco

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Can we start a Cummins swap info/questions thread?
« on: January 03, 2013, 12:32:21 PM »
Basically, I have a 95 454/nv4500 2WD with 60k miles. The motor runs like a watch, but I am not going to deal with 4-6 mpg when loaded. I bought this vehicle for one purpose, to haul my rock buggy and camper, or to haul broke down cars that I occasionally buy.

I am moving forward with a diesel swap, 12 valve Cummins, I am hoping I can compile info here for our style trucks, and hopefully get some questions answered. Then do a build thread while in progress.

So to start Cummins choice:

It seems the 12 valve was built up to 1998, the 199(5?)(6?)-1998 motors have the P-pump which seems to be more desirable as they make and handle more power better. Also, the newer motors have a higher HP rating.

So buy a motor, first question is fitment:

Looking at the one swap I can see into a 3500HD, and several 2500/3500 swaps, it looks like the crossmember needs notching and that is about it. Autoworld makes motor mounts, but for the cost they do not seem that difficult to build yourself, gen 3 dodge (24 valve) mounts are said to be a stronger firmer mount.

Adapting to the trans:

The NV4500 will need a Dodge bellhousing, used they are hard to find but out there around $250, new seems to be in the $475 range. Our slave cylinder is on the passenger side, Dodge is driver, can the line from our slave be replaced with a Dodge style, and then a Dodge slave be used?

Accessories/Gauges:

This seems to be a no brainer, if you run the factory ECM and remove un-needed wiring for the old TBI setup you can retain the factory gauges. AC and Alternator can be mounted with Autoworld brackets, or home fabbed ones. Alternator gives Tach and Voltage, Factory AC compressor wil function as normal in regards to cycling. Stock 6.5 fuel sender can be used with removing the factory pump and putting a hose in, then you have a gauge. Factory oil pressure and coolant temp sensor can be adapted to Cummins motor and retain gauges.

Radiator/Intercooler/Condensor:

It sounds like the factory radiator is sufficient, a Dodge intercooler will go in front of it and the condensor with trimming of the core support. Does the intercooler go in front of the condensor?

Mechanical or electric fan:

I see electric fan swap threads, but some say it is not enough to cool the Cummins when towing, any thoughts?

Things I am currently unsure of,

Hydroboost:

There is a setup on the Cummins with I assume a gear driven vacuum pump. Is the 3500hd plumbed so the HVAC does not need vacuum as we have hydroboost? Can I find a Dodge motor with no vacuum pump and ready to run Hydroboost with adapter fittings to our system.

Wiring the Cummins:

I have found some info, but still researching, concerned about heater grid, water in fuel, wait to start systems etc.

Second tank setup:

I have one tank, do I plumb in a second tank with a dash controlled pump to auxillary fuel the primary tank when driving? Rather than dealing with a tank switcher, maybe the tank switcher is easy to add.

TBI wiring:

Once the swap is done and running, it would seem that I could go to the ECM pins and remove the TBI systems completely to clean things up.

Turning the motor up:

The key here is reliability, thinking a simple reman turbo, the HE style, a fuel pin/plate mod, timing, and possibly send the pump out to have it preventatively rebuilt.

Clutch:

Everyone online is running clutch setups that will cost more than what I will spend on a motor. For a normal guy with maybe a HE turbo, govenor spring and pump turned up slightly, how much clutch do I really need?

Speedo:

Where does our truck pull the speedo signal off the NV4500 at? Mine is currently INOP.

This is a good start, I am pretty obsessive so I will link, add what I find. I am thinking I am going to take my used engine, and replace all the gaskets, clean and paint the block, KDP etc. I will link relative how to's documenting those steps.

Can anyone help me with all this?

Rayjon237

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Re: Can we start a Cummins swap info/questions thread?
« Reply #1 on: January 12, 2013, 11:30:22 PM »
Ok lots of questions..  

I did the swap with 95 cummins motor with a nv4500, in my crew cab hd.


Cummins choice

I found a low mileage 95 175hp motor,  looked a a few found one out of a wreck that was well maintained.  

my mods include a #6 plate and 3k governer springs,  I also used a he351 on a freightliner bus manifold,  

lower horse motors have smaller injectors and can get better mileage if tuned properly.  mine gets 20mpg at 70mph and is over 9k lbs empty..  

Fitment

I notched the crossmember but others haven't, I did it so I could use the gm fan shroud, with the stock dodge fan,  now this took some work but was worth it to me.  I used a 89-93 fan drive and fan belt.  it moves the fan up and back, giving another inch of room.   I notched about 4 inches, so I could get the oil pan off in the truck if needed.  I marked the crankshaft centerline in my 6.5 and then cut so the cummins sat at the same location,  you will also want to measure the driveline angle so it stays the same.  
motor mounts was easy just 1/4 wall 3" tube with some flat plate.  used first gen dodge isolators.  with the mass of the HD frame its smoother at idle than my dodge was...  



Adapting the trans,  

being that yours is a 95 you have the same problem I did,  oddball one year only nv4500..  what I did was swap to a dodge input shaft,  machine the dodge bearing retainer 1/8 (the input bearing register in 95 was smaller than 96-)  and then redrill the lower holes in the case to match the dodge belhousing,  If you can find a 96 or later HD nv4500 all you have to do it swap the input and bearing retainer and it all bolts up.  Don't forget to check the endplay in the trans after you swap the input..(not hard to do)

clutch hydros are easy use the dodge stuff and just lengthen the rod from the clutch master to the clutch pedal about 1/2 inch.. 

Accessories

No need for the autoworld brackets..  the A/C compressor fits in the stock location with the HD frame,  

gauges are easy just adapt the fittings,  mark the harness real well before pulling it apart..

I ran the dodge alternator, with a ford regulator,  didn't tap for the tach as I plan on swapping to a motorola semi alternator and will do it than..

A/c required custom lines ,  word of caution replace the evaporator and heater core in the dash while you have it apart,  they are GM junk and go bad..

Radiator support,

I had several days figuring out how to fit it all,  I used the HD  radiator in the stock location,  If you tow heavy in the mountains its worth it..  but is adds some work to get it all to fit.  cut and reinforced to mount the 94-97 dodge intercooler,  and then made a bracket for the condenser and the hood latch in front of that.   Call me and I will explain further,  I made it look factory but it would have been alot easier to cut it up and use the dodge stuff...  


Hydro boost

bend the lines a little and it all goes right in,  will have to T the return off the brake booster and the steering pump but other than that just put the hoses on the Dodge pump..

vacuum pump..  make sure you cap it off,  it wont hurt it as its oil lubricated,  if you dont the vacuum pump exhausts into the crankcase,  can you say blowby..  it will pressurize the crankcase like you have alot of blowby..  just cap it off..  or plug it...  


fuel tank---  100 gallon bed tank works..   but I can go over 400 miles on the stock tank now...  


Turning it up,  Competition Diesel is great,  just go read what they are doing,  stock motors with 215hp injectors can make over 400hp with a stock injeciton pump,  just tuning and adjusting the turbo and fuel curve..  

Clutch ..   I am still running a stock dodge clutch with about 90k on it,  they will amaze you just drive like an adult..  its like my FJ40  yes you can break stock axles on 35's but if you drive like an adult they will live, awhile?...   My plan once it goes is to change to a Fuller 6 speed and a 14" medium duty clutch,  about half the cost  of aftermarket dodge clutches and I get a stronger setup when I'm done..   What I have should last another 100k or so with no issues,  I'm only at about  320hp,  and it runs good..

Speedo

comes off the tail housing of the nv4500 there is a small computer box above the computer behind the glove box  that compensates for gear ratio and tire size.

I PM'd you with my Phone number give me a call,  I will give you any info I can,  I highly recomend the swap,  and its worth the look when you pull away going up the mountain from some guy who just spent $$$ on his duramax,,    
« Last Edit: January 14, 2013, 04:52:53 PM by Rayjon237 »

Rayjon237

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Re: Can we start a Cummins swap info/questions thread?
« Reply #2 on: January 12, 2013, 11:41:27 PM »
oh on the fuel lines,  

the stock gm stuff has alot of poorly made bends and the stock lift pump is a restriction,  i ran new 1/2 hard lines from the tank,  made a new pickup in the stock sending unit,  then used the 3/8 line as a return eliminating a bunch of bends,  the stock gm lines are 3/8 feed and 5/16 return, dodge stuff is 3/8 and 3/8,  and from what I have read they become a restiction if you run over 40psi of fuel pressure at the injection pump.. that was the reason for the 1/2 inch line..      

the gm lift pump wont flow enough fuel for a stock cummins more or less a modified one..  My fuel pressure was fine at idle but would drop hard under any load,   cost me less than 100$ in lines and good Parker hose use the Hydraulic rated stuff,  about 3$ a foot but more than worth it,  its good for 600psi with the correct fittings..  

hope that helps...
« Last Edit: January 14, 2013, 04:55:07 PM by Rayjon237 »

Rayjon237

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Re: Can we start a Cummins swap info/questions thread?
« Reply #3 on: January 14, 2013, 05:01:11 PM »
another area that makes a big difference with a cummins is rpm,  I ran 3.54 gears in mine which puts me under 2k rpm going down the highway.  if i drive 55 it gets great mileage 22-24mpg as it puts the motor where it is most efficent,  1600-1700rpm,  but if you keep it under 2k rpm going down the road they do real well. 20mpg at 70mph..  over 2400,  and you will see your mileage go down 4.10 gears  and 75mph  is   15-16mpg

KingNothing

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Re: Can we start a Cummins swap info/questions thread?
« Reply #4 on: February 12, 2013, 05:18:08 PM »

Adapting to the trans:

The NV4500 will need a Dodge bellhousing, used they are hard to find but out there around $250, new seems to be in the $475 range. Our slave cylinder is on the passenger side, Dodge is driver, can the line from our slave be replaced with a Dodge style, and then a Dodge slave be used?


Im not sure if your truck has the NV that you want.  I was under the impression that the GM NV4500 that you are able to convert to a dodge style all had internal slave cylinders.

The early gm nv4500's have a lower first gear and you cannot put a dodge input shaft in them.

I was pretty sure 95 would be the newer style NV...... but the 3500Hd could have been different.


I would look into that to be sure that you can convert it to a dodge input shaft

Rayjon237

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Re: Can we start a Cummins swap info/questions thread?
« Reply #5 on: February 13, 2013, 09:49:28 PM »
I should have explained more on the nv4500,

 the 92-94 trans have a lower first gear and the dodge input does not fit due to the gear ratio, bearing retainer diameter, input shaft length, front bolt pattern and front bearing diameter.

the 95 is oddball the gear ratio changed but the front bearing and bolt pattern stayed the same(can be adapted but more work)

96 and up the trans are the same gm and dodge the only difference is the input shaft length and bearing retainer.

best setup is to get a motor and trans out of the dodge then use he dodge front half and  gm back half, as most nv4500 will need to be rebuilt.
« Last Edit: February 13, 2013, 09:58:57 PM by Rayjon237 »

Rayjon237

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Re: Can we start a Cummins swap info/questions thread?
« Reply #6 on: February 13, 2013, 09:54:11 PM »
another option is to use a fuller fso 6 speed out of a medium duty,  nv4500's arn't the greatest and upgrading to a fuller gives you a 14" clutch that is cheep and a trans that is rated for up to 800ft/lbs at 40,000 gvw..  and they fit in a 3500hd.

mdemco

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Re: Can we start a Cummins swap info/questions thread?
« Reply #7 on: March 14, 2013, 11:54:01 PM »
So what exactly needs to be done to the NV4500. Doing some quick reading, input shaft, and machine the bearing retainer?

I also would need to buy a bell housing.

My NV4500 only has 62k on it, but I am worried it has been abused. Really noisy till it warms up, reverse grinds unless I shift into 2nd then reverse, and 2nd and 3rd don't slide in, they kind of clunk in.

I am worried it may be getting worn.

What about one of the big autos out of a school bus maybe? I will look into the Fuller.

someotherguy

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Re: Can we start a Cummins swap info/questions thread?
« Reply #8 on: March 15, 2013, 08:54:37 AM »
I'd wonder if it has the correct lube in it.  Someone may have serviced it and used the wrong lube.  It wants specifically - GM Synthetic Transmission Lubricant, part # 12346190 - you'll need 4 quarts, maybe a little more.  I think the 4 quart capacity is for the regular NV4500 used in lighter trucks than the HD's, the longer tailshaft housing might cause it to take slightly more.



Chrysler dealers also sell it, part # on the trans label too, shop around for the better price.  Expect to pay around $18~$22 a quart, though.

This is re-labeled Castrol Syntorq LT - not to be confused with their Syntec motor oil, and for the most part, you can't buy it in a Castrol bottle anywhere as it was developed for the OEM's.

Richard
06 Silverado ISS / 06 Silverado SS / 06 300C SRT8

mdemco

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Re: Can we start a Cummins swap info/questions thread?
« Reply #9 on: March 15, 2013, 06:07:52 PM »
I just did a clutch and serviced the trans when it was installed, it has the correct fluid.

Rayjon237

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Re: Can we start a Cummins swap info/questions thread?
« Reply #10 on: March 17, 2013, 03:10:37 AM »
even if it had  the wrong fluid it at one time,  the syncro's are carbon fiber and when new make it shift nice but run anything other than syntorque and you will start loosing synros quick. 

to answer your question dodge input shaft,  machine the bearing register so it fits the gm trans roughly 1/8 inch of diameter where it fits in the case,  once the bearing retainer is mounted may have to slot the bolt holes a little,  get the bellhousing 2 of the 4 bolts will line up on the front of the trans,  mark and drill two mounting holes in the front of the trans case.  use all the dodge stuff for the clutch hydros and back of the motor,   hope that helps,  check your pm and give me a call,  I could write a book on what I did to my truck
« Last Edit: March 17, 2013, 03:28:43 AM by Rayjon237 »

mdemco

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Re: Can we start a Cummins swap info/questions thread?
« Reply #11 on: March 17, 2013, 04:27:27 PM »
So, the option here is to buy a new

bellhousing, for around $500 judging by ebay,
rebuild kit $200 ebay
Input shaft and bearing
Clutch and hydraulic assemblies

Then I need to gut my NV4500, mill the input bearing retainer in the case to accept the Dodge bearing and shaft. Then add the two holes for the bell housing.

The advantage of this is a basically rebuilt trans, but I am going to be at least $1k into the thing.

How fancy of a clutch do I need to buy? Those things are spendy.

Is the NV4500 my best trans choice? I want a stick, I only want to do all this once.

mdemco

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Re: Can we start a Cummins swap info/questions thread?
« Reply #12 on: March 18, 2013, 02:06:34 AM »
Did a bunch of reading. I am going with a Fuller. I will sell the NV4500 while it is still worth something.


esbstuff

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My swap...
« Reply #14 on: April 07, 2013, 01:56:49 AM »
94 truck, 97 engine, 98 Dodge/Chevy hybrid transmission...

Pic 1: Some places show pictures of less cross member missing, but if you want the engine to go in and out easily, this is where you need to be.  The engine mounts are from the donor truck that had 1” blocks welded to them, then welded to the frame.  Oil pan gasket looks easily changeable in truck without much issue

Pic 2: Spray bomb rebuild of the 5.9. At 158K what else can you do? You either use the GM NV4500 and change the bell housing, input shaft (and main shaft depending in year) or use a Dodge NV4500 and just swap the GM tail shaft housing...

Pic 3 & 4: One custom lower alternator bracket and a GM alt fit quite well. Tech tip: A GM alt keeps the tachometer working and you don't have to wire up the Dodge external regulator.  Just swap out the GM pulley for the Cummins pulley and go… I used an 87 7.4L hd alternator…

Pic 5: Lower heater hose adapt-a-fitting. This little fitting allows you to run an OE Dodge Belt AND a GM alternator.

Pic 6 & 7: A rice burner intercooler and related piping makes for a quick install. This intercooler has the same cooling and flow as an OE Dodge (97), but it is shorter but wider than OE and fits nicely in between the frame rails.

Not shown (but important!) is you will need to use a first gen (89-93) Dodge Cummins fan pulley and hub assembly.  This will help with the clearance issue, radiator to fan. Also plan to shorten the front driveshaft piece 3” and remounted the shifter boot and hole back 3 inches. On the clutch,  I used South Bend Clutch parts. Part #Hyd-X-1.50 slave cyl assembly and a towing single disc clutch rated at 400 HP, part number 13125-OK. You will find that the clutch pedal will set a little lower than stock, but it will function fine.

The only thing I really didn't like doing this had to scab the lower radiator hose in. I used a GM 6.5 radiator and an OE Dodge upper hose, but I couldn't find a lower hose that would work. I ended up using a 06 Cummins lower hose adapted to a GM 6.5 lower hose.

The engine has had some tweaks... 3K springs, 50 Hp injectors, fuel plate slid back some, the pump turned up a some and the timing has been bumped a little too. With the addition of these mods, the 5.9 will turn 2700K easily so the stock diesel  gears work great. It will run 85 mph no problem.

I average I get 12 mpg easily, with mostly in-town driving.

You can expect to spend with 2 people, 3 days removing a 6.5 and installing a 5.9 if you have all the parts.. You can expect to spend 2 hard days with the wiring getting everything to work, including the grid heater and water in fuel light. I used all GM senders and all the gauges (including the tach) are dead on.
« Last Edit: April 07, 2013, 02:01:37 AM by esbstuff »
1994 3500HD 5.9L (Cummins) NV4500 4.63

 


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