I'm trying to figure out which Carter pump is the right one for my truck. Cummins lists a 3990082 for 98-99 and a 3990105 for a 00-02. What is the diifference in lift pumps between model years? I don't know which Carter is the best. Some are saying it is a HP4108 and some say it is a 4601. Can anybody enlighten me on which Carter # to use? Any feedback would be appreciated.

 

I just replaced my "99" yesterday with #3990082.

 

CTD

Your #3990082 matches my second replacement pump I purchased from Cummins.

That one lasted around 7 months. Didn't know it was headed south 'till the isspro went in.

I went back with an attempted warranty replacement at least. I was willing to eat the labour as the rig is out of warranty.

Much to my surprise Cummins replaced and installed FOC. This one is a Cummins/Carter 3990105.

I think the ports are opened up-less resistance??

Been a real strong unit so far. Have'nt been able to sink the needle past 12.5 psi

 

Taz,

I guess you are saying the 3990082 and the 3990105 are interchangable? The only difference is the port size? Is there anything else that makes the 3990105 a better pump?

I know, lots of questions I'm just trying to get to the bottom of this. Was the Carter # on the box you got from Cummins? Can't figure out which Carter is the right pump.

 

This may or may not be of any help. While in the Summit Racing on line site I came accross a Carter fuel pump. It is rated for deisel. It is a rotory vane type with a 100gph flow with 18psi and 3/8" in and out. Pump cost is $87.88 and the relay kit is an additional $26.95. The part no. on the pump is CRT-P4601HP and the part no. on the relay kit is PRF-50102. This might be a better or as good of unit for the CTD to run on. Might work.

 

I found a Carter fuel pump at Summit Racings web site. It is rated for deisel and has a flow capacity of 100gph with a pressure of 18psi. It is a rotary vane type and looks like it would work on a CTD possibly. Their part no. on the pump is CRT-P4601HP at $87.88 and a relay kit part no. PRF-50102 at $26.95. Possibilities maybe for the Dodge CTD? They have a picture of it and it looks close to the one on the truck.

 

CTD NUT
98-99 have a wire pigtail about 6" long and the 01-02 dont, the wire harness on your truck will require a 6" jumper for the newwer model pump if it dosent come with it. My new pump didnt come with it so I just lengthened the wires but there is a proper jumper wire available. IMO the pumps are the same other than that.

 

The 3990082 should have had the pig tail in the box unless some ingrate took it from you. I've got a spare here if you need one.......in fact if you let me know where you live I'll send it to you if you send me your old pump. I'm tearing down old LP's to see if I can figure out why they fail. I wanna build a better pump and sell the idea to Carter.

 

Hey CTD,

I guess if you're gonna help a guy then help him!!

Sorry man, my info is not as complete as it could have been.

The 2 pumps are interchangeable as I have had both on my truck. The internal port sizing was info from another thread. Buddy said he took the two apart and noted this physical difference.

ratsun, you are absolutely right. I forgot about the pigtail. It is needed (if not for ease alone) for the 3990105 on a '98.5

IMO the 105 is a better pump, time will tell.

I can't help you out with Carter #'s other than what I posted earlier. Cummins did the replacement and I didn't see the box, just the P/N on the invoice with a big fat $0 at the total.

 

No problem, Taz I appreciate any info at this point. It appears the 4601 is the Carter # for the correct pump. At 100 gph, I think this is adequate free flow, but others have suggested a pump around 140 gph would be better. This seems high to me - any thoughts?

 

CTD,

I think the VP needs all it can get and then some. If I had the coin it would be a FASS and kill this issue for good

Is your pump bad or are you preparing for the "inevitable"??

You might want to get some gauges on that bad boy soon, don't know how long that '082 was pushing zip before I got mine.

Good luck

Check your PM.

 

Oh yeah, the guages are coming - I will not bomb without them. I checked the fuel pressure when I bought the truck and it was fine, but like you said, I am preparing for the inevitable. The FASS looks cool but the cost is certainly prohibative for me and living in Ontario where the roads are white with salt ALL winter long, I do not like where the FASS is mounted. I wish you could put a FASS under the hood - it just won't last mounted on the outside of a frame rail where I live. The truck also sees some mild offroad use towing my Jeep to remote campsites.

I agree 140 gph would not hurt anything as long as the pressure is not too high. But 100 gph is still moving ALOT of fuel and I don't think Carter makes a 140 gph pump. I will be getting a Wildcat Maxflow kit when the Comp box goes in and see what happens. I just want to have the right lift pump on hand so I don't have wait or search for a pump when it dies. I will be keeping a spare in the truck so I don't get caught in the middle of no where with no fuel pressure.

 

CTD,

I hear you on the FASS. Got the same concerns. Don't you just love our winter roads in Ontario

Must be a place to "shoe horn" that sucker in under the hood. Haven't really looked yet but I bet there's a good chance there's room when the stock filter and LP are out.

Hmmmmm gotta look into that.

 

Yeah, let me know if you come up with some type of underhood FASS mounting. I wonder how well it will perform sucking fuel instead of pushing it. The FASS is very large - I have my doubts about it fitting under the hood.

 

I just bought my LP from Napa it's a Carter with a life time guarantee. It's no fun to replace but beats $500 or $600 for a fass