Looking for some group feedback on options for rebuilding the various powertrain components. My '99 Disco is right around 160k miles with a bad head gasket. Normally I'd just change it out and drive it, but we've made some changes to the garage this year which leaves me with the Disco as my only vehicle. Instead of buying something new, I'd rather throw some money at it and make it a real solid truck. It's something I'd rather do once and not worry about again for a while - engine, trans and t-case included. Obviously there's the basic rebuild options, but there's some other stuff out there that interests me. I'd love to hear what others have done, if anyone has taken this route.

Engine: Right now I'm close to pulling the trigger on a TWS (Wedge Shop) build, after talking with them a bit. It's not cheap, but gives a lot in terms of performance upgrades and power. Does anyone have experience with one of their builds in a D2, good or bad? Any reliability concerns versus a Turner engine? Should I drop the extra cash to move to a 4.6L? Currently not interested in an LS swap option.

Trans: I can't find any decent sources stateside for a refresh/rebuild of the 4HP22. I'm inclined to send it to Ashcroft along with the t-case - my only concern being warranty issues on something like that. Has anyone has an Ashcroft-upgraded trans built out? The trans feels ok right now, but my friend's '04 just gave up the ghost at about the same mileage. With the abuse my truck has had over the past 25 years, I'd rather just have it done along with the engine.

T-case: I'm just gonna send it to Ashcroft. My current one is junk - replacement from an '03 with no CDL and the previous owner seems to have run it dry for a while. I have a decent '04 unit that I can send out for a reseal and ratio change to match the 33" tires. Also considering adding the ATB.

If anyone knows of good resources in AZ for any of the work, I'm all ears as well.

 

I think your drive train probably has quite a few miles left on it without the major work you’re talking about.

 

I don't doubt it would go another 10-15k easily with just the HG replacement, but the contents of the last oil drain were not very reassuring, nor was the subsequent oil analysis. 2500 miles on the oil showed a good amount of aluminum and iron. Definitely a fair bit of gold and silver metal in the catch pan as well. Mild bottom end knocking when cold - goes away somewhat when warm. Seems like it's lived a pretty hard life with little to no upkeep. It was even running the original 3/98 dated thermostat when I got it last fall.

My timeline is one of the factors at play here - I have a borrowed car to drive over the next few months before the D2 becomes my only vehicle for the foreseeable future. Downtime is much less convenient after that. I'm fine running the trans for a while longer - I know those can go for a long time. But it's hardly the largest expense I'm looking at here. Seems easiest to just do it all at once, if I do go ahead with everything.

 

Looking at the oil like you’re doing is a great idea. Good luck with your overhaul.

 

Daggone shame. Bottom end oughta last 250k miles minimum (if maintained). Same for the tranny and tcase. It must have been abused, like you say.

If you're willing to drop the dough, sounds like you have a solid plan together. Curious why you're not considering an LS swap with the amount of money you're considering spending? There are a couple different options around, and you're sure to increase reliability and power to boot. There is a company that does turn-key installs for what I consider to be pretty reasonably, for what you get. In the 15k ballpark from what I recall. I've seen one in person and it was a super clean job. Guy that owns the truck raved about it.

If you're going to be sending tranny off to Ashecroft, I'd find a cheap used 4hp24 instead of sending off your hp22. Might even talk to them about sourcing one in the UK instead of shipping yours across the pond, could probably get a used one over there for price of shipping from the States.

Whatever route you take, nice to see some folks starting to do some "restoration" type work to these D2s.

 

I've got three drivers over 215k,one has 260, one has 240. They had pretty decent maintenance. Had dozens of others apart, most are fine relative to the bearing and ring life. My 240k If your oil pressure is good.Most issues were caused by the ****ty OEM thermostat and PCV valve. Did oil analysis on my 240k mile truck 10 years ago, it wasn't great. Still has great oil pressure. A simple bottom end rebuild and ring set would likely get you another 150k easy.

Have had to rebuild exactly one HP22 and even then it was only the front clutch. Buddies 04 had a torque converter go bad. The transmissions are generally very durable, I would get an early HP24 if you can, 03 model. I have seen more 04 transmissions go bad than the early trucks. They basically don't wear out, other than the front clutch issue which is well known and related to a factory seal fault on the early ones. I personally believe the last of them had quality issues with the TC's

I have spoken to the wedge shop as well as the guys in the UK that do builds and both seem very knowledgeable. 215hp and 300ft-lbs stock, the torque is very comparable to a 4.8LS, but at even lower rpm. Factory cam is very low rpm torque focused. You can get 300hp out of engine with a cam that shifts the torque peak, but honestly I don't think you will feel it. I have driven LR3 (300hp) and LR4 (375hp)and the LR3 didn't seem like it had that much on the D2 and although the LR4 moved pretty good you wouldn't mistake it for my Camaro or my 79 CJ with the 360.

 

I've done a few other cars with engine swaps and more highly modified builds. I'd rather stay stock with some light performance upgrades this time. Emissions is also a factor for the time being.

I'll be hauling a buddy's dead 4HP24 home this weekend, so that would be a decent core to send off. TBH the upgrade cost for Ashcroft to mod the 22 to a 24 isn't all that bad either. Thankfully I have access to rock bottom shipping rates through work - last I checked it was quoted out at a couple hundred to send both units over there.

I'm definitely in the rare camp of borderline restoration on this truck. Chalk that up to my OCD and desire for perfection.... Unfortunately I probably bought the worst candidate for that, but like most cars I buy, I get far too attached to it and want it to be perfect. I'm only justifying it by telling myself that having one of the first D2s made makes it worth it for some reason

Zero record of maintenance here. Let me know what you think of the UOA attached. Most stuff I take off is original, so basically 25 years old at this point. PO used it exclusively for beating on in the desert I'm pretty sure and kept it driving as cheap as possible. I was 100% committed to finding a '99 Kinversand, so that's what I get...

Do you think it's better to rebuild a dead '04 HP24 (May '04 production) over modding a allegedly good HP22 with the uprated parts? That one seems to just have a dead oil pump. Fluid looked great still. If I do the Wedge build, the 24 is probably a must. They claim 280HP/280TQ on the 4.0 - they test with a 4-barrel on the dyno though.

 

That looks way better than what I had on mine 60k ago

 

I agree, your numbers do not look all that bad. A little above average in a couple places, sure, but remember you're talking about parts per million. Those are still very small numbers. Were it mine, I'd throw a head gasket in it and run it. While you've got it apart and easy access, go ahead and throw a new crank sensor in it.

As for tranny and t-case... killer shipping price. As far as upgraded 22 vs standard rebuilt 24, I'd call em up and ask. Sounds to me like 6 of one, half dozen of the other. Won't go wrong either way. Like Extinct said, these are really robust trannys. You're starting to see a failure here and there, but really they're very uncommon. I've dealt with a lot of bad trannys, but for all the D2s I've owned I've never had one with a bad trans.

Now, if you decide to rebuild the motor anyway - there is no way I would spend that much money and not upgrade to 4.6.

 

You still running that engine without major work? Makes me feel a little better. My UOA was done on the oil from the PO - no clue what it was or what viscosity. He told me "what the owners manual calls for", but that could be basically anything. I found a quart of Castrol 10-30 in the back, but hopefully it wasn't that. Way too thin for the desert out here. I was hoping to get another sample in with proper oil and more gentle driving, but the head gasket had other ideas.

It actually runs great, especially after new injectors. Obviously fixed the leaking down/flooding issue and even got rid of the slight idle hiccup. Cold starts are still a little rough, but I think the IAT in the MAF is no good. The temps looked about 15 degrees high.

I'm really only concerned about two noises it makes - the cold idle knock (not too severe) that almost goes away when warm, and this weird metallic noise that you can hear when revving the engine in park. As the RPM falls through 1800ish there's a weird higher-pitched metallic noise. Almost like a jingling noise.