3rd Gen Dodge Cummins auto trans question

Doc Mayhem

Observer
I looked at a 2007 Dodge Cummins 4wd quad cab with an auto today and am unsure about the transmission. Originally I wanted a manual and have been looking and they are rare, there were a few a couple hours away but by the time I had time off they are sold or they wanted top dollar, as in 4-5 grand over book. Anyway I drove this 2007 with a 5.9, that has almost 60,000 on it. Drove straight, good brakes, a few imperfections here and but no rattles, and clean underneath. The transmission has me concerned. I started it just by turning the key and not letting the grid heater warm up and it started right up with a small amount of white smoke, I did this because it is supposed to be a good indicator of whether the ijectors/pump are working well. So it idled for a minute or two and then put it in drive and went to pull out and it felt like it was in neutral, and didn't move until the engine hit about 1,500 rpm approx. Also the vehicle didn't creep while idling. It seemed to drive well and shifted fine, but then when I got back and played around with going from park the drive I could now feel the vehicle switch into gear and it would creep at idle. This seemed strange to me and am thinking this tranny is on its way out? The parking space was on a very slight incline and the motor was cold when I first pulled out, but shouldn't it have been creeping forward when I first put it in gear? Does this seem normal?
 

Regcabguy

Oil eater.
The Dodge autos don't have drainback valves and most of the fluid will drain into the pan overnight or after they sit awhile. You always want to idle them in neutral for flow.After starting, put them in neutral first and usually they take right off. The 48re's are a really sturdy unit if you limit the power to 50-75hp over stock. I love this manual I've got,but if I'd known the superior track record of the 48re over my last 47re on the '98.5,I'd probably have gotten the auto. An aftermarket valve body and torque converter will firm them up and help them to last even longer. I never use the grid heater here in San Diego unless it's under 40*. Super simple setup compared to glowplugs. Heat is an issue offroad when you're crawling in hot weather. Waiting in line at the border on a hot day in my DTT built auto wasn't fun either pulling it in and out of gear to cool it down. As mentioned,an auxillary tranny cooler especially one with a fan helps tremendously.
 
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Terrainist

Explorer
I don't think this is right on target with your questions, hopefully you can get something from it though.

I have a first gen diesel (93') with an automatic trans. When I put it in gear, it's in gear right away, no waiting. When in drive, it creeps forward if I am not on the brake.

Automatic transmissions mated to diesel engines in the light duty trucks (dodge, ford pick-up trucks) have always been problematic due to the torque of the diesel engine. I'm sure you have found this in your research.

However, if you go the automatic transmission route (I had to...have a bad back) there are somethings you can do and look for to better your chances of getting a good functioning automatic.

Pull the dipstick and check the color of the transmission fluid, make sure it is the appropriate color. Drive the vehicle enough (15 miles?) to get the transmission fluid at it's optimum operating temp and check the level with the dip stick. Has it been ran with not enough or too much trans fluid in it?

Automatic transmissions need to be serviced regularly, mine every 12,000 miles. That is trans flush, band adjustment, filter replacement. Look for a vehicle owner that stayed on top of the maintenance if possible.

An extra transmission cooler is a plus, overheating can kill an automatic. I have an aftermarket transmission cooler hooked up besides the factory one, and given the number of times and the situations I have heard that thing start running...I am of the conclusion they are needed.

At the most, this is speculation, somewhere around 100,000 miles is the life expectancy of a properly maintained and used automatic transmission mated up to these Dodge and Ford diesels. If you can get that out of it, your doing good. Look for a rebuild in the past, or know how many miles are on the transmission.

Hope this helps.
 

Terrainist

Explorer
Also, you can take any vehicle you are interested in into a transmission shop. Have them pull the pan, see how far out the bands are, if there is any metal in the pan or the filter. Should be around $50, $75 dollars to have it looked at.
 

angusdevil

Adventurer
That's normal. All three 48re's I've had in the truck have done that. The fluids have just drained down to the pan and are getting back up into the workings of the tranny. Nothing to be concerned with.
 

Metcalf

Expedition Leader
I would say get what you want....

If you want a manual just search more and wait. If your not in a hurry you will find what you want at the price you want.

Personally IMOO. For durability and reliability with stock (ish) power motors either transmission will do ok. The 48re could generally use a better converter and a throttle body that allows 'better' shifting. Line pressure needs to go up as throttle application does, I think most performance autos just up the line pressure so it always shifts firm. 90% of the time you don't need a super firm shift or pressure on the clutch pack. It only when your really going for it....or pulling heavy.

While I like manual transmissions with a Cummins. They always seem to be too short between gears. If your not in a big hurry and don't mind shifting a lot then a manual isn't that big of a deal. I think one downside to manual transmissions is that if and when you ever have to let someone else drive your truck. It always sucks to watch someone, especially those who you care about, grind, bang, and slam your trans while taking a few thousand miles off your clutch.
 

Overdrive

Adventurer
My '04.5 was doing the same thing after it sits for 2 or more days. 80K miles on it now. Took it to the dealer and they said it was due to the transmission filter being dirty/plugging up. Had them service it, and all is good now.
 

Doc Mayhem

Observer
Thanks for the quick replies. It makes more sense then that it ran fine and then functioned as I thought it should when I got back. I am torn on whether to get a manual or auto. I have to say I liked the auto more than I thought I would. I traditionally always had manuals and my mustang is, the truck does have the manual transfer case lever, which is important to me.
 

deserteagle56

Adventurer
It is a weird feeling, putting the tranny in gear but nothing happens for a little bit. That's the way my 04.5 has been from day one. Just give it a minute or so to circulate the oil and things will be fine. Never had a problem with mine and I pull some heavy loads (but the engine is totally stock).
 

jp0863

Observer
I looked for 4 months before I found a manual trans. Check dealers in Texas, they seemed to be able to get one overnight when I finally asked someone. Had my 05 with a g56 2 weeks later. All I can say is if you get it shipped to you, find a good reputable company and check BBB for any complaints. Mine was a headache and a half getting it here, but Texas is also cheaper than California too so it was still worth it.
 

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