Inline Cummins 6 concerns

[wagoneer]

Being happy with my choice of vehicles I have been looking at late 90's Dodge pick-ups with inline cummins 6 any of you have experience with
servicing these. 4 x 4 manual tranny models are rare birds.

 

[highdesertranger]

non electrical cummins are great motors a true truck engine. however I got a little story. I have a buddy that works for Caltrans(Ca Dept of Transportation). they had many of the Dodge 4x4's in their fleet. he said, " they were great strong motors never had any major issues with the motors, however the truck would fall apart around the motor." he said, "when the trucks were retired the motors ran great, but the rest of the truck was ready for the junk yard". so I say be careful. of course the way they build vehicles now, I feel vehicles are disposable. this is my opinion. I sure wouldn't want to totally rebuild a computer controlled vehicle, It would be cheaper to just buy another. highdesertranger

 

[squatting dog2]

Being happy with my choice of vehicles I have been looking at late 90's Dodge pick-ups with inline cummins 6 any of you have experience with
servicing these. 4 x 4 manual tranny models are rare birds.

Cummins is virtually indestructible. You will find the generic Cummins in all kinds of equipment. (dresser dozers and motor graders for example) Simple to work on and parts are easily available. I stick with the manual trans as dodge did have an issue with auto transmissions.

 

[Rustyvan]

311000k on my 03 Cummings haven't touched the motor yet.with cold air intake, 5 in exaust extra ,100 horses programmer just shy of 500 poneys,if I keep my foot out of it.or not towing can get 1000k out of 130 litre tank. The only things I've done to the truck is a clutch an breaks

 

[29chico]

If you want a rig with a cummins and a body that will stand the test of time google "4bt grumman bread truck".

The cummins 4bt is a turbo 4 cyl version of the turbo diesel 6bt that is in the dodge trucks.  The grumman body is an aluminum step van.  Lots of those step vans were converted to cummins 4bt's.

 

[masterplumber]

I have a 2012 Ram 2500 4x4 with a 6.7 cummins and manual trans. No doubt it has all the power you'll need - almost 400 HP and 800 ft lb of torque from the factory. That said, I would look for a low mileage 5.9 if i had the time. The 6.7 doesn't get near the mpg, and I've heard that from everyone I've talked to with one. Mine averages 11 - 12 mpg most of the time, with an absolute best of 15 once. Also, Dodge still hasn't fixed any of their quality control issues. Mine seems to be pretty reliable now, but before I had 60,000 miles on it I'd done $5000 worth of repairs, including a complete clutch system and most of the front end parts.

Once you fix the issues that should have been addressed at the factory they seem to be long running trucks. A good friend has a 1999 2 wheel drive manual trans that is pushing 300,000 miles and still runs great. He gets 19+ mpg around town and up to 23 mpg on highway trips. He just went to TN to buy a 2006 5.9 4x4 with an automatic (he's tired of shifting) and so far loves it. He averaged 19 - 20 mpg driving it back to CO.

 

[Canine]

The company I used to work for uses step vans with the Cummins. The old engines were great and they loved them, but the new computer controlled ones have been quite a headache. "Fussy" was the word they used. All the stars need to align for it to work well; if one star is out of alignment, then performance suffers badly.

I'm a big fan of manual transmissions, but automatics are a good way to go for diesels. Diesels shine when they are running one speed. They have a relatively narrow band of power and automatics accommodate that better than manuals.

I'm not afraid to shift, but 6 gears in a manual? If I were doing more highway driving, then manual would be fine, but if I were predominately in town driving, then I would prefer automatic.

Automatics are becoming more common across the board. The Tundra can be had ONLY in an automatic. No joke. There are still a fair amount of manuals out there.

 

[masterplumber]

Actually, Rams are the only full size pickup still sold in US with a manual - one of the reasons I went with one. I prefer the manual for towing, mainly for the larger gear selection while climbing hills. Diesels definitely have a narrower power band and more gears help keep it in that power band. But automatics have come a long way, and also are starting to have more gears, so the benefit of a manual for pulling and even mileage is getting smaller and smaller each year.

 

[highdesertranger]

ok here is my observations on automatics and diesels. off road they suck. they waste all that low end torque that diesels are great for. they slip way to much especially in low gear while trying to crawl over ruff terrain. you have to give them way to much throttle and get the rpms up way to high when trying to crawl up hill. then when you are going downhill especially with the stupid computer controlled transmissions you are always in too high of gear and find yourself riding the brakes. some of them when you down shift they actually upshifts causing fast acceleration on steep declines. my old gasser with a granny gear manual outperforms todays autos hands down for off road driving. the cowboys I work with all have diesels with autos, Fords, Chevy's, and Dodges. they are all the same. my 2 cents. highdesertranger

 

[ZoNiE]

The manual transmission is a piece of crap. I have a buddy with one, and he has had it rebuilt a few times. Cannot tow his trailer in 5th or over 55MPH.

 

[highdesertranger]

The manual transmission is a piece of crap. I have a buddy with one, and he has had it rebuilt a few times. Cannot tow his trailer in 5th or over 55MPH.

-Zonie
well that doesn't surprise me at all. that's why I a big fan of my old rock crusher SM 465. highdesertranger

 

[masterplumber]

Yeah, you definitely need to be careful with the newer manuals. Aluminum cases that can warp, dual mass fly wheels etc.. I've replaced my entire clutch system including the flywheel with a solid mass unit. The early version of this trans, and the later version of the 5 speed and an overdrive that was low enough that people would tow heavy loads on overdrive. This would put too much torque on the trans and stretch parts etc... causing failures. Mine likes 5th until about 65 mph, then 6th. If I'm towing anything heavy I only use 6th if I'm cruising along at 75 and not pulling a hill. I still worry though. South Bend is working on a brace for the trans, similar to the ones people used to run on drag cars. I figure if I ever do break this trans, and I still want to keep the truck, I'll try and swap in an Eaton 7 speed. Probably before that I'll just switch to a medium duty truck.

HDR, those SM 465 units are about as good as they get, just no overdrive, and "I can't drive 55!". Off road I actually like the SM 420 better, for it's even lower granny gear, but it might not be quite as strong. I have manuals in my "86 Ford, F250, '79 CJ7, 2004 KLR, and 2012 Ram 2500. The only one I worry about is my Ram. And of course that's the one I drive every day for work and take on long trips. : ( The old stuff may have needed more maintenance, But they were generally built stronger when it came to drivetrains.