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Thinking about getting back into a 6.5TD

Sentinelist

Active Member
Messages
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Location
North Texas
My account still works! A hello from several years ago (and shout-out to Leroy in particular!). The rig in my signature you might remember was bartered for some major perimeter fence work at my property back in 2017, after not using the rig much or being able to justify it versus an offer I couldn't refuse back then. These things happen. I have been diesel-less and truck-less ever since. Land Cruisers, utility trailers and a rooftop tent have been playing the supporting role in the interim.

Just now getting the thought back to stick another GMT400 back into that spot for doing truck things, but this time as a Suburban K2500. Classic truck project that I can use for ranch duties while tweaking it in my spare time and use for some camping trips. Was initially figuring my odds on just getting lucky if I found a clean 454 gasser, but I may have lucked out in finding a clean 6.5TD. It's a 1995 with 280k+ mi. on it but a 2-owner/single family owned rust-free southern states example with few minor needs I can address later and listed for a great price as such. Am waiting to hear back from the seller for additional questioning. A few up-front general concerns:

1. Is getting back into an original 6.5TD, with a DS4 no less this time, still a reasonably wise move here in fiscal 2023? Or should I stay away these days, give up all hope, and go back to looking at 454s or assume a Duramax fate? I haven't kept up (here, obviously) with the 6.5 scene since 2017 at least. It's great to see some old familiar names and the 6.5 activity here still, Leroy's site, and a few others I remember that appear to be still in the biz.

2. My last OE 6.5TD threw a rod or something at about this same mileage. I had it swapped with a mil-spec used Optimizer 6500 in 2015. It seems these and P400s are a lot less - if at all - available anymore? I just read the P400 thread here about no more civilian sales. What are the options these days when the OE mill goes south?

3. No idea if the PMD has been relocated on this one yet, which I would do immediately and then buy a spare along with going down Leroy's recommended checklist, but I'd also be planning a DB2 conversion sooner than later after I got this one home. Am thinking about flying out and driving it home from the east coast in a few weeks if it passes a PPI and doesn't have any glaring major needs. Some technicals from past experience I'll have checked out there first.

Anyway, I'm looking at what appears to be a dusty unicorn I can shine back up pretty quickly, really miss having a 'real truck' diesel around with that sound, but wary of the time and changes that have gone by as I look forward. Not sure if a 6.5 is still a feasible game to play or if I'll have to continue waxing nostalgic instead. No interest or budget for a Duramax or newer truck- this would once again be a 4th vehicle for me for spare duties that will sit outside (but under a cover probably). Any feedback would be appreciated while I figure out next moves- had to come back to you guys first. Cheers and thanks for everything here over the years.
 
WELCOME BACK.. come on now you know you miss hearing the whistle of a diesel....lol
My opinion.. since you're not going to use it for a daily driver but more around the ranch, I would assume fuel economy is not the biggest of concerns.. although it is always important. 6.5 that's running good get's pretty decent mileage for a truck.. not great but not terrible.
Advantages are they're pretty damn easy to work on. Fairly dependable as long as you take care of them.. and I would assume plenty enough power for anything you're going to do around the ranch...
Personally you couldn't give me a dirty Max... Just not a fan. A 454 is a good engine but they do wear out and they're pretty damn hard on fuel..
Personally I can't imagine not having a truck in my yard I always figure if you have a truck you can make money.
But some of the other guys who can chime in and give you a better advice on the situation that I can.
But once again welcome back to TTS
 
Welcome back @Sentinelist !

For whatever my opinion is worth here goes...

1- A DS4 is on borrowed time parts wise with it being discontinued, BUT the 1995 is a much easier year to do the DB2 swap on as it was the last year of the single stat crossover (also ideal in some corners) and has zero clearance issues with the DB2 throttle bracket. I also like the 1995 and down being OBD-1 which makes it easier to swap in tunes, or even have multiple tunes available at once compared to the 1996+ OBD-2, should you want to stay with the DS4

I may be wrong but the K2500 suburbans may have also come with the wider 3.5" rear end drums, which is a cool feature not found on the truck K2500s

2- The original rig is high mileage, but seeing as how it was a family vehicle and not a work truck it may have led a pretty easy life. Can the existing owner send you videos of it running with the oil fill cap removed to see if there is any blow- by?

Optimizers are readily available new, just P400s are NLA. So you have good replacement options and a bevy of upgrades available should you ever need/ want to throw in an upgraded engine

3- If driving home check the oil cooler lines BEFORE hitting the road, and if they look anything close to stock/ original consider installing upgraded lines before the long trip. Hate to see you stranded mid trip with a seized engine

I am probably biased but my persepctive is that older, simple & mechanically injected diesels may take more attention to maintain, but parts are WAY cheaper, from injectors to fuel system components, and easier to work on. If you already know and appreciate the 6.5, as the saying goes, the devil you know is the devil you stay with 🙃
 
Hey, good to see ya back.
Easier to find a bag of money no one wants than a p400. GEP Keeps rolling on optimizers so they are more plentiful- but 18 year old boys keep overheating them in hmmwvs. So perfect take outs are rare- better found in complete hmmwvs sold and getting the mega builds done. A member here just got a hmmwv with under 10,000 miles so the great finds do exist.

On the ds4/db2 conversion, used to be junkyard tcm on old trucks was cheaply found- not anymore. But a few stand alone trans controllers exist now, and you can really play with settings in them.

Prices on 6.5 stuff has went up, but not worse than anything else.
 
It's a 1995 with 280k+ mi. on it

It's cheap for a reason. It's lived 3 lifetimes (of 100K) now. Remember the parts black hole they become at 200K? No matter the engine: everything is worn. Seats. Good luck getting seat parts.

How long do you think the differentials are gonna go without some serious $$$$ to rebuild or junkyard swap replace them?

1995 was a special sort of special with every DAMMED thing that could go wrong with HVAC did and would. Control panel, wiring connector meltdown, to the R4 compressors jacked up on R134A pressures... now optionally add a rear evap with little debris screen that's a bastard to get too. Seriously you have overcome PTSD the R4's gave you? If so do share how. 🤪

At least the 454 has room for a better compressor with off the shelf brackets.

Rear evap ... Did I mention the Rear Air Diesel Suburban was the first to go? Kept the pickup much longer.

Not getting good parts is one reason I gave up. Non-stop rebuilt (patched maybe: likely just some cheap paint applied) parts I got to change out till I found a good part. The lack of a good shortblock to bolt nice heads too just sucked.

You blow an engine: at least they are still in production as used one are rare to find in rebuildable condition let alone "good". No I doubt your budget will allow a new engine and of course it will need a turbo too.

The ATT is discontinued. I read that better turbos have appeared since.

The local parts store hardly knows me anymore. However the new truck payment is less than I spent there every month...
 
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I still think the old girls are plenty viable in 2023, still cheap to buy and keep on the road. I just drug home 2 more since thanksgiving...lol 1800 bucks in both,and one drove home.

I definitely wouldnt DB2 swap a factory DS4 rig, I happen to like, prefer, and seek out a DS4 over a DB2.

In my opinion, with Leroy and Quadstar and other good vendors, these old girls will be going for many years yet. They still build new 6.5s, only slight concern is the DS4 longterm, but im confident if there is enough demand a supplier will pick up some parts needs. my optimism comes from Ag equipment, you wouldnt believe how well supported some low production models are.

I have a 06 Duramax, but the "cheapness" of the truck overall robs me of happiness. lol the Duramax GMT800 has performance, the 6.5 GMT400 has personality. 9 times out of 10 personality trumps performance for my needs. :)
#1 thing is dont kid yourself into thinking these are a new truck. treat it like the half wore out 190 hp IDI that they are and it will treat you well. Too many people drive like idiots with the pedal on the floor for long periods of time and whine when it blows up. If driven gently they are very capable, I just drove my stock 95 K2500 across Wyoming at close to 5 tons over factory tow ratings and it did great. slow and steady!

Id shop a little closer to home personally, TX is full of cheap rust free rigs, I salivate at the FB marketplace offerings down there. :)

Good luck!
 
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