Epsilon Plus

I spent $1,600 shipped for the full swap including skids and one-time-use TTY bolts/nuts. The only thing left to buy is a couple bolts for mounting the rear of the transfer case skid when I mock it up and decide if I can tap threads or use through bolts. Figure ~$2,000 if doing it from stock to finished with a set of Bilstein 5100s.

newdude has confirmed they are not part for part the same. The diesel 10 speed has a few things inside it that have increased strength. Prob cryo shafts or an extra clutch or something. As can be expected of a unit designed to hold twice the amount of torque.

There is plenty of power options available for the L8T for steep prices. If HPT can break the Global B HD truck it will open that market to you. Tuning isn't going to do much to stock worth the cost. However, if one was to put the Stainless Works 2" headers/full exhaust on and walk the LT2 cam in and tune on 91, the engine would churn out 550+hp off the crank. The blower kits on 20-23 ECMs are putting down 700tq on 5.5psi stock everything else. For a tow rig you wouldn't want the cam/exhaust route unless you wore ear plugs full time. Any type of increased power route is going to drain fuel out of the truck like there is a leak in the tank so not really a good idea for a business rig either. You may enjoy the throttle response improvement of the lameo pedal commander/Pulsar LT route if/when they are available for 24+ (might be already, I dunno) but it's not a tune or power adder. CamGTP, I swear I've seen you around since the LS1Tech/LS1GTO days. Us ol forum fogeys are still hanging on!

Many a good tire gets it's bad reputation from the OEM stock versions of it. The OEMs use cheaper quality rubber and a generally crappier tire to save a fortune. These tires will have the same name and look of their retail counterparts but perform as much as 50% less. Michelin Defenders get a bad rap from Super Duty guys as they are or were stock on those. Firestone Transforce, while being a crap retail tire, is flaming hot garbage in OEM form on Ram HDs. If I was going to run a non-aggressive tire, the Defender LTX is king. The aggressive category belongs to Nitto and Toyo.

B&W 7" adjustable is perfect.

Yes. Almost everything directly ports over. The only thing that didn't was one 10mm bolt for the top brake line bracket. The other bolt on the side holds it on just fine. Someone could zip tie the unused top bracket hole or Loctite purple (low strength) the side bolt if truly concerned but I really don't think it's needed. The bore for the hole is not cast into the ZR2 knuckle. Oddly enough, all other dowel holes and bolt holes are there and work perfect. Unused on the new UCA is two holes on top where the ZR2 re-routed lines go. You can see them used on joe97281s pictures as he was going through the process of line conversion to run the bulky DSSVs. Cheers to 215robert as we were kind of going at this blind not knowing if it was really going to work and be stuck at the last second after bolting all that stuff on, but we made it through. FWIW he has a diesel so this swap is confirmed for either set-up, same P/Ns (except DSSVs).

Truck is pretty high now. At almost 6'2" I can stand against the back tailgate and my chin is only an inch higher than the top of the gate. For the price of the parts and the drive as stock results, I really don't think there's a better way to get the 37s and proper look out of these trucks. Who's doing it next?

Ground to fender lip stock I was ~39.5 and with just the ZR2 lift on 265/75 (31s) I was about ~41 5/8 now I'm at ~44.5. My keys must be up a little compared to stock ZR2 because I'm even with the back and stock ZR2s are about 1.25 higher in the rear. My UCA ball joint angle is flat and perfect so with this lift I've achieved exactly what I sought out. A perfectly leveled look on 37s with no aftermarket wonk or adverse driving characteristics. In my opinion this set up is the best way to fill the wheel wells, the perfect lift height, and the best way to make it all last 200,000+ mi like stock. For speedo I'm using the Pulsar LT. Running 50psi with lowered TPMS warning threshold, speedo corrected to the 37s, and throttle lag gone on level 3 response setting. It's like I have a brand new vehicle. Love it.

Front & rear ZR2 lift complete! 37x12.5s on GM 18x8s. No rub!

ZR2 and 3500 use the same rear U Bolts. The ZR2 uses a 1.5" lift puck, and the 3500 has an overload spring pack that probably measures about the same so that could explain the rear at least. Dunno about why a dually to dually would be so much higher unless one or the other had the keys turned or came out of the factory out of Z Trim Height spec.

Truck is done. I'll post pictures when I ditch these lame embarrassing 31" stockers and put the 37s on. Anyone have access to the factory Z Trim Height specs for a ZR2?

Instead of the blowers that just came out one could likely do this cam, springs, and 2" stainless works headers/true duals and a tune. The advantage of the blower would still be single kit, not opening the engine, and forced atmosphere at altitude. Its great to have tuning but the costs are bleh. I remember when ol HP Tuners was like $350 or something haha

A look at the increased droop travel stock passenger side vs ZR2 driver side (both ZR2 diff drop brackets in). No torsion bars in. Stock is 8.25" from lower ball joint nut to ground. ZR2 6.5"

Tips while they're fresh: You can take the whole brake caliper bracket off and leave the caliper and pads...etc intact and move it out of the way. SUPPORT IT! so you don't rip a brake hose. As you can tell from my above pic, you don't need to bother with separating the ball joints of the UCA/LCA and you can take the UCA/Knuckle/LCA combo out as one piece. For the steering shaft, pry against the shaft and hit the knuckle to pop it loose LINK. Concerning the diff drop bracket, the service manual has you reinstalling the top carrier bolt and tightening, the main bracket bolts and tightening, THEN the other too lower carrier bolts. Thread everything in but leave it loose until it is all in. You'll have to use a flatblade through the lower carrier bolt holes and a pry bar in various places to meander everything into alignment. The brackets ride on rubber cushion mounts so if you tighten like the service manual sequence, the lower carriers will be off. The brake dust shield can be put on backwards (lol). Make sure it faces front and allows you to put the rotor on BEFORE you go through the hassle of torquing the hub bolts (doh). Also, can confirm that the 20-23 brake line brackets, speed sensors...etc are a 100% fit to the 24 ZR2 knuckle. You can see the spots where they probably mount the 24 stuff but all the holes and divots for the 20-23 are there! I'll chime back in if I think of something. So far sockets/wrenches needed: 10mm, 15mm, 18mm, 21mm, 24mm, 36mm (axle nut). Get a good split beam torque wrench up to 250lbs. Also get used to having to just ugga dugga some stuff because no way any torque wrench is going to fit on some of that stuff. Cheers.

You'll need a 1/2" drive 18mm, 21mm, & 24mm socket and open end wrenches. You'll also need a 1/2" drive 24mm deep socket for the LCA nuts and a 21mm deep to make the diff bracket easier. Wobbles and extensions a must. So far the only rear PITA was getting the 4 hub bolts back on. The knuckle and axle don't give crap for room for a socket to fit snug over them. Unfortunately, some of this stuff has to be torqued with a wobble or extension. Yeah, I know but it is what it is. Just about done with driver side. Stopped to do left diff bracket since one of the bolts for it is in the way of an LCA bolt. Real peach. Good news is with only 19k miles, everything is coming out easy. Torsion bars dropped out with barely a wrist wiggle. Cheers.

It's going down boys!

Just saw this today. Apparently at the end of last year GM Performance dropped an L8P crate engine. Looks to be just a cam (and likely valve springs) only L8T. Same intake/exhaust manifolds, compression...etc. It really showcases the monster potential of one of GMs greatest engines. Cam only and jumping from 87 to 91 it bumps from 401/464 to 523/543. That's a monster gain of 122hp and 79tq from a moderate cam size (relative to "big" aftermarket cams of 240+ duration and .600+ lift). Cam is from an LT2 P/N: 12736191 other part number change on the crate engine is the cylinder heads but that's very likely only the stronger valve springs to support the increased ~.50 lift. Duration increases from 193/199 to 218/231. That exhaust duration should make the truck THUMP at idle through the big 3.5" exhaust. Impressive. Most impressive. https://www.chevrolet.com/performance-parts/crate-engines/l8p

My buddy just sent pics of his 24 WT. Has the plastic steering shield but no front diff/oil pan skid. Also no tiny transfer case skid. If you want those without having to add them after (they are cheap and the holes will be drilled for it) tick the Z71 box. My buddy will be getting my stuff as I change to ZR2 gear.

ND is the real MVP for all that legwork but know you have contributed to the delinquency of an HD. Hopefully the ones he takes off find a home on some poorly optioned truck that had the baby mirrors stock.

Not just pre-drills. It's a complete crossmember under the bed between the frame rails and a 7 pin plug in the bed. If you ever plan to do a 5er or gooseneck, it is worth it to order that up front.

Unless you have a big tongue weight or payload on the back, they won't soften the ride if that's what you want. They will control trailer bounce and help control rebound. You could take a shock out of the back and drive around empty and not notice a difference. The issue is the 3,000+lb payload leaf springs. Unless they are under some load, shocks aren't going to soften a spring that's not even compressing. That said, if you can't find 24+ part numbers, 20-23 will work. There's no changes under the truck that would necessitate a different P/N shock from 20-24. So far, our sleuths have uncovered only different brake line and speed sensor part numbers for 24+ to clear the ZR2s DSSV shocks, and they may only be for ZR2 24s.

On the 20-23s the radio bezel had to come out. If it's worth $22 or so to you go to AC Delco TDS and buy the 3 day subscription to the factory service manual. PDF print everything you ever think you'll be doing, torque specs and all while you're in there. PITA but worth it.

This is awesome. Going to make one! Thanks.

I think he meant he ordered the bolts but they got lost in transit. I've now got everything except the transfer case skid, the brake lines and the wheel speed sensors unless there is some phantom part numbers I don't know about. The only thing I'm nervous about is I'm hoping my brake lines/hoses and wheel speed sensor brackets/sensors can be used with all the new parts. Not opposed to getting the ZR2 wheel speed stuff if I have to and IF it will connect to my factory harness but I REALLY want to avoid opening the brake system. I'm anxious to start tearing into it though. Edit: Oh, I also need to track down a torque wrench that goes to 244ft lbs without costing more than the entire swap for those axle nuts lol

I think the OP isn't around on this site anymore. He was the farthest along with this swap. Anyone else trying it out?