Which diesel-powered Dodge?

[Josiah Rojas]

So I decided I am going to get a diesel powered Dodge.
The question is: Which one?

-Obviously it will be a 4x4.
-I prefer the 250(2500) over the 350(3500). I don't plan heavy hauling, per se.
-I prefer the body style used all the way to '93. My brother has '99 Ram Sport 1500 so I'm okay with the "new" body style so I can rub it in his face. I mean, what are brothers for?
-Automatic or manual transmission? I prefer the manual but which one will handle engine upgrades better? Nothing wild just reliability and simple bolt-on stuff.
-from what I understand the 4BT(a) ('91-'93) and later the 6BT ('94-'98.5) 12-valve engines are pretty simple in function and setup. I prefer simplicity.
-intercooling is really cool

These are preferences. Although I prefer the early body style I am willing to go with the "better" (I know they are all Cummins and I have nothing to worry about) engine and other options. I pose this question here because you guys know a LOT about these trucks and what can I say, I value your ideas and opinions. I plan to do further research on the TDR forum. Thank you.

[MoparNorm]

Here is what I know about 1st Generation Cummins
Best fuel economy, no inter-cooler, 727 trans is OK, 46RE is too weak, early Getrag trans bad, NV4500 good.
Now, that being said I suppose you could swap a later 48RE automatic into a rig, but a 727 will hold up too.
The 1 Gens got great fuel economy, but they were low on power, about half of what the last High Output, 5.9's and new 6.7's have.
That's most likely why the mileage is so good, I have the least desirable, 2nd Gen, a weal CA version, no HO allowed here in my year, a weak 47RE auto, the bad lift pump (the Bosch VP44) and a myriad of other weaknesses, it happens to be the best truck I ever owned, trouble free, great fuel economy, decent power, I love it, so go by condition, price and let your gut be your guide, it's not uncommon to find cream puffs if you are at the right place at the right time, such as a guy that just came upon misfortune and needs to sell now, a senior who used his truck for towing his RV, twice a year, and can no longer travel..
Many issues present great opportunities, Marty found these trucks within a few months of each other, they looked brand new...

[Josiah Rojas]

Thanks for the info, Norm.
Those are really nice and clean looking trucks. I really like the blue one.

Josiah

[Gordon Maney]

It is my understanding that there is a late, first generation truck that has the intercooler.

[MoparNorm]

Thanks for the info, Norm.
Those are really nice and clean looking trucks. I really like the blue one.

Josiah

I believe they are the same year, one SRW one DRW.

[Josiah Rojas]

Gordon, we must have been typing at the same time. I was also under that impression. First it was the 4BT and then at some point became a 4BTa before being replaced by the 6BT.
Norm based on your description if I go with the older body style I should go as late as possible, '93? And I should probably stay away from the auto just to minimize future problems in that department.

Josiah

[MoparNorm]

It is my understanding that there is a late, first generation truck that has the intercooler.

That may be, I'm not current on them, were they all turbo'd?
My memory is that the intercooler was added later, but still in the 1st Gen??? Or..were they all turbo'd and intercooled? Seems to me that a big deal was made about the 2nd Gen trucks having the intercooler, but perhaps it was just the fact that they had a bigger intercooler?

[Josiah Rojas]

Can you help me?
!st Gen: '89-'93
2nd Gen: '94-'98.5
3rd Gen: '98.5-2001

The 4BT (3.9L) was used until '94 when it was replaced with the 6BT (5.9L) but they were all "12-valve" until '94, right? The 4BT is a four-cylinder and the 6BT is a six-cylinder?

[JimmieD]

The 3.9L 4B, 4BT, 4BTA were never offered in Dodge trucks. That's an engine found in many delivery step vans plus countless industrial applications including tractors etc. Some were used as stationary engines, powerplant stuff, not immediately suitable for vehicles and possible EPA hassles, plus continuous speed power curve due to injection pump.

6B not used in Dodges that I know of, that a non-turbo engine, normally aspirated. 6BT was the first Dodge offering, as a turbo'd 6B, with Bosch VE piston injection pump and diaphragm fuel lift pump [to injector pump]. Capable power at about 150-170?, ridiculous reliability and easy to work on with no computer required to run engine: 2 wire hookup for Starter and fuel stop solenoid, plus normal alternator wiring.

Aftercooler cools pressurized air from turbo, pre-injection. This allows larger injectors, different spray patterns and higher power/torque output without high Exhaust Gas Temperatures or EGT's. EGT's are the worst enemy of diesels, representing combustion chamber temperature. Above 1,300* one enters an area where in seconds pistons may melt, head totalled and engine scrap metal etc. Aftercooler reduces these temps by cooling the forced induction charge going to cylinder, before fuel is injected.

Whatever diesel you buy please purchase a Pyrometer which monitors EGT's. Simple install.

All non-intercooled can be later fitted with an aftercooler fairly simply, but it can get somewhat pricey. Aftercoolers run for about $50 on up, and there's still some hoses and fitment issues, fairly simple though. With fitment of aftercooler the 1st Gen Cummins, '89-93, can be taken to very high power levels without great risk of incinerating engine. Easy gains of 100 HP with some screw twisting and minor mods, if an aftercooler is used.

Larger [later] turbos may be swapped in, again allowing for reduced EGT's while turning up the screws. Later stock turbos are fairly cheap, because those guys discard to upgrade theirs still higher. I regularly see turbos for $50 - $75 - $100, on up to the moon. Often requires some relatively simple piping mods. Turbos themselves can be upgraded also, such as the excellent HTT kits coming in various stages, or 'hybrids', or compound 'dual] turbos.

Easy to get 2nd Generation power out of a 1st Gen, while maintaining the ultra-simple Bosch VE rotary piston injection pump and being relatively free of potential electronic & computer problems. 1st Gens are probably the most reliable, except for some potential torque converter problems in A-618 autos used for hard pulling or towing, but fairly easily fixed. Shift kit and converter swap makes it a non-issue.

[Josiah Rojas]

Yeah, I was confused. I thought it strange that a 4-cylinder would be offered in a Dodge pickup and even stranger still it would also be a 12-valve (which would mean three valves per cylinder). For simplicity's sake I like the 1st Gen, I would either get an aftercooler or find one with it already installedand I could keep the older body style that way.
I think my choices are
A '92 or '93 W250 with 5-speed (this would be the Gertrag if I understand)
or
'98 2500 with a 5-speed (this would be the NV4500)

Jimmie are you saying if I got a 1st Gen with an auto I should look at a HD converter and install a shift kit and that should get me through any of the
"easy gains of 100 HP with some screw twisting and minor mods, if an aftercooler is used." That close to 100HP gains is fine for me because of the resultant torque gains as well. I don't need to go anywhere fast. The "screw twisting and minor mods," does that refer to new injectors, changing the injection pump timing, etc? I did read in some of the other discussions (I did look before I posted) you recommend changing a spring in the Bosch pump to a 3200 RPM if using a manual transmission.

Josiah

[JimmieD]

Yeah, I was confused. I thought it strange that a 4-cylinder would be offered in a Dodge pickup and even stranger still it would also be a 12-valve (which would mean three valves per cylinder). For simplicity's sake I like the 1st Gen, I would either get an aftercooler or find one with it already installedand I could keep the older body style that way.
I think my choices are
A '92 or '93 W250 with 5-speed (this would be the Gertrag if I understand)
or
'98 2500 with a 5-speed (this would be the NV4500)

Jimmie are you saying if I got a 1st Gen with an auto I should look at a HD converter and install a shift kit and that should get me through any of the
"easy gains of 100 HP with some screw twisting and minor mods, if an aftercooler is used." That close to 100HP gains is fine for me because of the resultant torque gains as well. I don't need to go anywhere fast. The "screw twisting and minor mods," does that refer to new injectors, changing the injection pump timing, etc? I did read in some of the other discussions (I did look before I posted) you recommend changing a spring in the Bosch pump to a 3200 RPM if using a manual transmission.

Josiah

Yes, a torque converter upgrade and possbly a shift kit. But, both give adequate warning most of the time, and this gives time to start feeding the piggy for that soon coming day. Shift kit mostly addreses more positive shifts and greatly reduces wear on the auto transmission, as quicker and more positive lockup. Torque converter is the power transmitter, prone to slippage of being burned up with heavy towing or abuse.

Many think that the stock Cummins diesel equipped Dodges don't have a stout enough converter from the factory, but these are also guys that run them real hard. Daily driver with little or no towing can do fine for many years.

The 6BT cummins does benefit from the 3,200 rpm governor spring, but it is far from mandatory. Its greatest advantage is in manual transmission trucks, to help fill in the gap between shifts due to some wide ratios. Not often need on auto equipped trucks.

The simple screw twisting can be done on a daily driver or other uses, but if towing is planned a turbo upgrade is a very wise idea before tweaking screws very much. I would certainly want to upgrade the turbo, it's fairly easy and cheap, if I targeted a 100 hp increase. With the turbo upgraded it is indeed easy to adjust the injection pump for way more power, safely.

Injectors sorta depends on exactly which truck you buy and therefore which injectors are in it. Some could use some help, some are really pretty good as is. Almsot any truck, regardless of which injectors, can have some considerable performance increase just from a quick turbo compressor swap and twisting a few screws.

If you're a guy that always wants a little more power out of a rig then you plan accordingly. If you have more moderate needs a 1st Gen is ideal, offering good stock power and the ability to easily add to that without going crazy. Further, if you want to go crazy on it, it can take it and has lots of room for fiddling.

Trying to sum up, they're great trucks as is with plenty of power, and more power is avalable quite easily. The penalty for more power can be breakage if you're not careful, so knowing where you're going helps: plan ahead. You may be able to drive some that are for sale to get a better idea of their stock power and plan from there.

[WARWAGON41]

JimmieD is dead on and really knows the Dodge / Cummins.
Between myself , my Dad and Brother we have had Cummins powered 4x4s since they came out in 89.
Most were traded in or sold with over 250k miles on them.
All but two had manual trans and ALL had been hopped up and spent most of the time pulling something.
The 89 was a great truck , it was turned up days after it was new and the 5spd grenaded a week or so later.
If i remember right early production trucks had a recall on the trans.
They replaced it the next day with the upgraded case at no cost to us.
Never had any more trouble with it.
Our 90 and 91 were great but the trans failed in the 91 at 130k miles.
93 had an auto trans and factory inter cooler .....no troubles just very low geared with the auto (80 mph at the gov.) even with 3.09 gears.
94 was a BEAST and very hopped up.
We hauled many loads at or over 29000 lbs gross up to 600 miles and more than once pulled a loaded 80000 truck and trailer back to the shop.
The only trouble was it would blow the hose of the inter cooler if you didnt watch the boost gauge.
Its still lugging around a concrete pump down in SOCAL.
96 was okay.....but the auto trans got weak.
The 98 and 99 were excellent but both had a lock nut come loose in the trans. A factory update cured that and there still going strong.
We did a 460 Ford to 5.9 Cummins Auto swap on a big Euro Coach motor home.......WOW what a differance !
Currently my Dad has an 05 1 ton 6spd with over 500 hp that he drives daily......he pulls a 38' fifth wheel or large equipment trailer and gets 25mpg hwy empty and 14mpg loaded.
My brothers 98 and 96 pull large goose neck stock trailers almost daily.
I have an 04.5 HO 6spd that is my daily driver and it is an awsome truck.
I hope it lasts forever.
My 2 cents worth of advice is.......
Pick one you like regardless of year. Most are great , some arent.
Just like any thing else two identical trucks can be differant , there were some that didnt have any power or got bad mpg exct..
Buy good oil , work it at lower rpm , dont idle it too much and it should last for a long long time.
The older ones 89- 98 seem to get better mpg , 98-01 do good ,02-07 some good ,some not so good.
Most things that add power to a cummins also add up to better mpg.
As for the trans.....the autos can live a long life IF you keep them cool .
A trans temp gauge and the biggest cooler you can find will pay off.
A manual trans will most likely do the best on fuel , and hold up great if you dont jerk them around.
They seem much happier with taller gears.....I would avoid the 4:10s unless you plan on running 35 inch tires.
Im no expert on these but I though I could share some opinions that might help.
Good Luck on your search . Im sure youll find one you like.
William.

[WARWAGON41]

Oh.....I forgot one draw back to the 89 - 93.
Super stiff ride , not unlike the flat fender Power Wagons we all love.
But hey.....its a real truck not a car.

[JimmieD]

Well, WarWagon, that's some mighty useful information too! Sounds like you come from a mighty fine family by my reckoning, good, sensible, down to earth Dodge maniacs.

Now this thread was from back in November, so I wonder if Josiah every found what he was looking for? Hey, Josiah, you out there in cyber land? Give us a holler!

Nice truck there WW, mighty nice. I have 4.10's in my Town Wagon 4BT with about 29" tires right now, with the NV4500 O'drive. It seems to give pretty good power, suits me, and cruising speed is fine so far. I don't drive much over the speed limit on interstates but if a guy likes to stay in the 80's or 90's they would be a little short for gears.

[MoparNorm]

My 2nd Gen with 4.10, runs just fine at 75-80, but she weights in empty at 9,000 lbs and really likes to stay under 2100 rpms...