Sorry to reply to this old post but I have the R2.8 as well. I’ve been wanting to delete the egr as well as getting it tuned. I was curious if you ever did and how it’s running so far afterwards. And did you just send in your ecm to get flashed or did you put it on a dyno and tune it that way? Thanks in advance! Texting me would probably be easier if you’d like. 541-six0three-8two5one
Cummins R2.8 97 TJ
- Thread starter nuffsaid
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Sorry to reply to this old post but I have the R2.8 as well. I’ve been wanting to delete the egr as well as getting it tuned. I was curious if you ever did and how it’s running so far afterwards. And did you just send in your ecm to get flashed or did you put it on a dyno and tune it that way? Thanks in advance! Texting me would probably be easier if you’d like. 541-six0three-8two5one
I'm in concurrence on this as well, though I'm really behind on my Jeep project. I put off stuff I have to do because I didn't have my new transmission and then my transmission came in and I installed it and same issues as before, so I'm still down until I get a chance to get the Jeep back in the garage and fix the stuff I knew has been wrong for a year or more.
I'm in the exact same boat where I want more power, but decided on the substantially cheaper and lighter AX-15 and obviously I don't want an EGR valve working and dumping in harmful stuff into my engine.
If you do get the tune, I certainly want to know how it turned out, though I'd probably lean more towards a modest tune with 360ish ft-lbs. I'm only going to stomp on the gas when I'm in 4th or 5th anyway, though I think 4th is supposed to be stronger, but I'm more likely to need more torque to go up a steep hill when I'm in 5th gear. Pretty much all the other gears, I've got quite a lot of torque for a Jeep and most trucks besides mainly the 3/4 ton and above diesel trucks. Even the big gas trucks don't seem to have great low end torque like the R2.8 does at 1,500 RPMs and up.
I'm in the exact same boat where I want more power, but decided on the substantially cheaper and lighter AX-15 and obviously I don't want an EGR valve working and dumping in harmful stuff into my engine.
If you do get the tune, I certainly want to know how it turned out, though I'd probably lean more towards a modest tune with 360ish ft-lbs. I'm only going to stomp on the gas when I'm in 4th or 5th anyway, though I think 4th is supposed to be stronger, but I'm more likely to need more torque to go up a steep hill when I'm in 5th gear. Pretty much all the other gears, I've got quite a lot of torque for a Jeep and most trucks besides mainly the 3/4 ton and above diesel trucks. Even the big gas trucks don't seem to have great low end torque like the R2.8 does at 1,500 RPMs and up.
I am running a TDI tuning box from Europe. It is a fueling box that plugs into the wiring harness and modifies the fueling, kind of similar to the Banks Derringer. If I remember correctly they claim around 50+ hp with this box, it has six or seven levels and I really only run level 7 for max power. The engine pulls hard and I have no issues. My egr hasn't given me any trouble for quite a while ever since the check engine light decided to go out and not come back. I clear the codes with my Autel scan tool and this code isn't set in history. I do have a couple other codes that are called permanent codes though. One of them is for engine overspeed, busting 3 foot deep snow drifts at WOT and I must have got carried away a little, I know I saw 4500 on the tach, LOL. If I was going to tune the ECM I would probably go with Power Toys from the cummins website, he seems to have a good tune and can remove the EGR from the ECM.
I haven't posted anything about my Cummins R2.8 swap in a while, because it has been delivering many smiles to the gallon. I have done a lot of winter driving in snow in rough country and the engine has been great. I did have an issue with the engine not getting warm enough when I was elk hunting and temps were around zero. I replaced the thermostat and all is well again. I am very happy with this swap! Great low end torque, and enough rpms on tap to spin the tires when needed and about double the mileage I got with the 4.0 gasser.
I haven't posted anything about my Cummins R2.8 swap in a while, because it has been delivering many smiles to the gallon. I have done a lot of winter driving in snow in rough country and the engine has been great. I did have an issue with the engine not getting warm enough when I was elk hunting and temps were around zero. I replaced the thermostat and all is well again. I am very happy with this swap! Great low end torque, and enough rpms on tap to spin the tires when needed and about double the mileage I got with the 4.0 gasser.
Thanks for all the great Info I really appreciate it. I’ve been in contact with power toys just haven’t decided what route I was going to go. You like that TDI box? Does it help with throttle response or throttle sensitivity? Have you noticed a big power difference?
98TJ_R2.8Swap
New Member
Lol I'm in Fall Creek. Let me know if you want a hand wrenching.
We're actually heading over to McKenzie today to recover a car dumped in the woods and do asbestos mitigation on another abandoned RV.
-Mac
98TJ_R2.8Swap
New Member
The TDI box has been doing a great job, they claim 213 hp and 369 ft lbs of torque. I run it on the highest setting all the time and don't have any issues. It moves my 5500 lb TJ very well, much better than the 4.0 gasser for sure. I don't drive on the highway a lot, but last year when I was hunting I drove it over a 100 miles to get some new batteries for my camper and with 35 inch mudders and 4.56 gears I got over 25 mpg and plenty of power.
4:10 gearing and 35” i get 21mpg. so that’s some good fuel economy on 4:56
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I am probably around 20 mpg running around town on short trips. The best part is in the mountains in 4 low where it easily uses 1/2 the fuel of the old 4.0 gasser and has gobs more torque.
I had to drop my 23 dually gmc off at the dealer to have some warranty work done and I towed my Jeep down so I had wheels to run around. It turned out that they didn't get my truck done the same day, so after putting on 114 miles scouting for an Antelope buck, I filled up to find out I averaged 18.5 mpg for the day of running some two lane highway roads and tons of two track dirt roads. Then I had to drive the Jeep 90 miles home and then back to the dealer two days later. 20 mpg+- was the result! It was hot and I missed not having A/C, but usually when I drive the beast it is cold out and I count on the heater. I drove between 60 and 70 mph and never had to shift out of 5th gear going up any of the hills on the highway. The coolant temp crept up a little bit to a high of about 210 on the way home, but it was 94F outside. Two weeks before the Jeep got a work out deer hunting when it rained over an inch. With both lockers engaged and the tach sitting at 4,000 rpms I made it up every mud hill I encountered!
I used to get info on the Cummins Repower forum and power toys was active there. Now I can't find the forum anymore, maybe it got taken down. When doing online searches about the R2.8 Power Toys pops up and bad mouths the engine. When I contacted them before it seems like their tune was close to 1k, but I am a bit leary to have someone make me a tune that bad mouths the engine.
Will Axis do a tune for you? Just because a company complains about an engine, doesn't mean they can't tune one. But they are likely more comfortable with Toyota diesel engines, which are supposed to be amazing engines that the US gov kept us lowly civilians from owning. Though we do have the 6BT and some other really amazing engines you don't see much in the hands of civilians overseas.
I've read their article and it's all baseless claims and rumors, because they somehow found an early, possible ISF2.8 from the Chinese market, which on so many levels is just setting yourself up for failure. Also YES it's going to be a PITA at some point when buying rare engine, this isn't conceptually difficult for most rational people. And what it really comes down to is that it's against their business model and for the Toyota crowd, I'd go the route they are going too. I drive my wife's Tacoma fairly often and every time I drive it I wish there was a diesel under the hood mainly just for the torque curve, because if that engine doesn't scream, you can't maintain speed without going downhill. Of course Toyota has some of the best small diesels in the world and they should have been installed in the US trucks and what diesel toys does is buy a half of a vehicle from overseas and then just bolt in the non US version components into the US version components and you've got a pretty nice and reliable rig. And we don't have those Toyota rigs because the EPA only wants the engines from the short bus they are carted around in and they have been putting their thumb on the scales for activists for decades to destroy the automotive industry or at least the US consumer.
Most people that do an engine swap should not do an engine swap. For the others, if you're in the US, you should probably do a gas V8 swap. If you're not in the US then you can just buy a properly equipped diesel 4x4 from the factory without the EPA gear on it for 30% less than ANYTHING even remotely similarly equipped in the US (When I was doing my swap and considering a new vehicle, a TRD Tacoma started about $40k and a Toyota Hilux, better equipped was a little over $30k).
Unfortunately for those of us that have worked with diesel engines and have become hooked by the way a vehicle should move and where an engine should make torque there are very few options. Basically nothing is great for the sub-half ton market that we can find. A TDI can scoot you around for a light weight rig, but it just needs more displacement. 4BT is a cool option, but it isn't as well mannered. R2.8 really is the only crate engine out there. And yeah it's expensive and if the unelected gov regulators that believe EV semis are going to catch on and you've got to work with them to sell your main product that keeps your company profitable, then you're probably not going to mess with a marketing gimmick of a crate engine, one that was gutted and should have been the R3.8, but that would have been even more cost prohibitive in the US.
Winter is back and my Jeep has turned into my go to town vehicle just because it is fun and good on fuel. Keeps me from putting so many miles on my dually. I am back to wanting a nice winter cover. I can get engine temp up to around 170 if I am driving around 60 mph in 5th gear. If I slow down much and have the heater on my engine temp drops down to around 120-140. Right now I have some foil bubble wrap between the grill and the radiator. Since the intercooler is also there, blocking it totally off with cardboard has given me some check engine lights for too high charge air temps, so just blocking the air from the grill is what I am after. I bought a piece of immitation leather and I am trying to decide if I want to drill holes in the grill for snaps. It has been pretty cold for the last couple weeks going below 0 almost every night. I am still scratching my head with my heater too. I get good air flow from the dash vents and also from the defroster, but poor air flow when I set the heat to floor. The other day I ran into town and the Jeep had about an inch of snow on the hood, after a couple of miles of driving the floor was covered with snow! I had the cowl off last month and cleaned out the heater box and duct work very well and all of the actuators seem to work. With all of the small 3/8 de air hoses I have on the engine, I think a fair amount of coolant bypasses the radiator. I think I am up to around 5500 miles and the engine does exactly what I want.
Jake kozlowski
TJ Enthusiast
Winter months I struggle with temps. Ran it in -15 the other day and maintained 180 at 70mph! Now when I go off the highway I was right around 165 and idle dropped down to 120ish. I run cardboard but it only blocks off my radiator and still flows air across the Intercooler. No engine lights.
Heat, I miss my 2.5L... the r2.8 doesn't crank out the heat for the cabin...
Sounds about the same as mine. I haven't really checked my fan clutch to see if it is free wheeling like it should be in cold temps. I just scored a hard top a couple of months ago and that is helping, but hot inside the cabin it isn't, more like luke warm. I might revisit my de airing lines to see if I can change them around a bit. My aluminum expansion tank is always full and the radiator is usually about an inch from full. I have my radiator overflow vented to outside air so that the coolant has somewhere to go if it gets too hot. I also need to experiment a little with running the heater in the A/C recirculation setting to see if I can cut down on the amount of outside air coming into the heater box.
In both cases here, if your engines are not getting up to operating temperature it is a thermostat issue, period. Specifically, the thermostat is not closing properly, or you have the wrong temp thermostat installed. The outside temp, driving at highway speeds, bad fan clutch, etc, have no impact on the minimum operating temp of the engine, which is what the thermostat establishes.
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