Welcome,

I would like to open a thread that will discuss the options of increasing fuel mpg’s as well longevity to the drive train. This is not just a performance or mpg thread! This thread is indicative to the long time owner and user not just running the ¼ mile or how many mpg’s one can get!

This should also include cost efficient ways of completing performance mod’s to accomplish these options. Back yard mechanics welcome! I would like to keep these upgrades under $500 per mod. Obviously there are going to be acceptations to the rule if this goes into large upgrades such as oversized torque converters, heads and ect. But let’s try to keep it simple and cost efficient. Remember that we are looking for mainly longevity, performance, horse power, torque, smoothness, and ideal overall toughness. Part numbers and brands would be very helpful.

Remember to include what models you are referring to as this will be used for searching for our users.

Remember the DIY thread stickied to the top of the section for instructions to many issues.
Do It Yourself (top questions and answers)


We are not responsible for any mishaps while you are wrenching, knuckle busting, throwing tools, kicking vehicles, stomping, whining, drinking, or possession of you or your rig by any entity....... Always consult a manual before attempting any wrenching and I advise you to stay within your skill set. If you’re expanding your skills, work on the easy stuff 1st to gain skills and the necessary scars on the hands to fall into the "working man/woman" category.

With that said lets open the door.

 

The HHO setup Thread will be the main discussion getting real improvement on MPG's All other upgrades that I have done, gains more power, but mpg improvement is neglible.

I will deduce that most OEM drivetrains aren't built to last long even with proper maintenance based on alot of users having lost their drivetrain in a unreasonable amount of miles driven. Any drivetrain rebuild, if built correctly will surely last the life of the vehicle if maintained properly going forward.

 

I believe that Spark Plugs should be replaced every 15k or one a year. This is one thing that always gets over looked. If you look into the cylinder after 60k with the OEM plugs or regular spark plugs you can see build up of deposits on the surface of the piston. I believe this in the most part to be unburned fuel and any resin from which as well as debris from any foreign source. Most of unburned fuel can be eliminated by simply making sure that the spark plugs are replaced by 15k or once per year. When installing new spark plugs remember that they need to gapped prior to installation.

Remember that our rigs like the OEM regular Champion spark Plugs. Champion Truck and Champion Iridium are also OEM replacement. Although some people like the Autolite 3923's in the 5.2L and 5.9L. I do not encourage their use. Autolite Spark Plugs are not recommended for use in the 4.7L. This is a good thread see:

Autolite Copper plugs ok?


DO NOT USE PLATINUM! Our motors were not set up for their use.

 

Another issue that is a power robbing feature is the intake of air. The Durango's intake of fresh air is located in the engine bay. The problem with this is the air is heated from the engine cavity thus warmer air is entering the motor by way of the throttle body. Warm air has less mass then cold air. One can do this very easy with limited capital.

See ram air for more details and ideas:
CAI
Custom made Front RAM air intake:
https://dodgeforum.com/forum/1st-gen-...ml#post1736713
https://dodgeforum.com/forum/1st-gen-...ir-intake.html
https://dodgeforum.com/forum/1st-gen-...e-ram-air.html
https://dodgeforum.com/forum/1st-gen-...-for-5-2s.html
https://dodgeforum.com/forum/1st-gen-...8-aem-cai.html

And don't forget this section:
Do It Yourself (top questions and answers) FAQ's


If one pipe's direct COLD air into their motor more mass of air enters the cylinder which creates more power. More power = more fuel mileage and less ware of the motor because it can stay cooler. Also it takes less force from the engine to move you rig creating more mpg's and less ware.

A drop in K&N filter is a $54 add on. This works well in our setups because more air can enter without restriction. Even if you just install a K&N drop in replacement filter more power can be made. It works a LOT better if used in conjunction with a cold air system. K&N filters can be cleaned and recharged so making them a great investment.


But even keeping an eye on the OEM filter every oil change or after wheeling or dusty road conditions can help.

 

My families last 3 new cars have been dodges and I must say that they have given great life for very little maintenance. Ill list the 3 cars and their few issues.
#1. 1990 Grand caravan 3.3L Lost its trans on the highway was warrantied and went on to go 250,000 miles with only oil changes, trans rarely and tuneups.

2. 1998 DGC 3.8L. Now at 95K other than oil changes and 2-3 trans changes, I just did the tuneup this summer and its running good.

3. 2000 Durango 5.2L. 171,000 miles and only oil and tuneups. Trans works great but a little delay hitting 2nd sometimes which i believe it needs a simple band adjustment. This has been the most neglected of our vehicles. Oil used to happen around 5-6k miles with conventional oil and the trans fluid has around 60k on it and is orange instead of red but doesn't smell burned.

Some people tell me that it is the luck of the draw when you buy a car but I find it hard to believe that my family has gotten 3 almost perfect cars in a row. I don't understand how the D lives on with its poor maintance history but i believe that it has to do with a good quality. None of our vehicles except the 90DGC (trans) have ever been to the dealer for serious work. The D went to the dealer for ball joints.

My dad is a firm believer in dodge and will most likely not stray. He is considering a new car in 6 months and will take a good look at dodge/chrysler before any other company.

Maintenance is key. I think my families success is that we do not take it to mechanics. We do all our own work so things like oil and trans fluid we know are the correct types.

 

Don't forget the other usual maintenance, the more often, the better if you can budget it. This recommendation is based on severe duty cycle changes vs regular duty cycle changes.
3k-5k synthetic oil changes
3k-5k paper air filter changes (non paper filters such as K&N, you can clean them but at longer intervals. I would suggest anywhere from 10-20k depending on the outside enviroment where you drive your Durango.
12-15k Transmission fluid changes. (include the transfer case for AWD/4x4 models)
24k differential fluid changes.
yearly or bi-yearly radiator fluid change

 

Transmissions can provide years of great service if one maintains their fluid changes and filter changes. Remember to only use the CORRECT fluid. See your owners manual or go to DIY on the main 1st generation page and there is a link so you may download one.

Towing and even every day driving can rave havoc on your transmission. If performance is what you are looking for OR less ware for you working D and also daily driver then let me suggest a shift kit from www.transgo.com

They are the best in the industry only advanced by a customized valve body in the transmission which usually includes a Transgo shift kit modified if completed right. Most trany shops can install them for about $300 to $400. They take the slip off your clutch packs and linings and also bleeding leak issues inside the trans. Also holding your shift points will hold in better pattern. This will add years to you transmission.

Also a transmission cooler is recommended if not equipped OEM which is usually located between the condenser and the radiator. Transmission coolers help keep the transmission cool which keeps ware down even in the most extreme conditions. Transmission fluid is oil and oil doesn't cool down as fast as water and for that one is defiantly recommended. These should be installed on the line returning to the transmission from the radiator so as they are the last stop before returning.

Deep well transmission pans are also available to help in cooling by adding volume to you transmission fluid. Most will run you about $150. They will add about 2 more quarts and yes it makes a difference. Keeping your transmission cool and working properly will increase mpg's and also power not to mention costly repairs.

 

Does the differential really need to be serviced that often? My D with 170k on it has never had the diff touched. It has never given any trouble.

Also is 15k factory recommended for the trans? Haha these posts make me feel bad for the neglect that my truck has received.

 

1. In my opinion diff changes I would do at 30k or bi-yearly with full synthetic lubricant. If you have a limited slip rear end don't forget the friction modifier. Front diff's are open gearing so no friction modifier is needed. Also if you drive in deep water change the fluid very quickly as water my enter the diff's and damage gearing, bearings, and ect.

2. Trany fluid and filter changes once a year or like he said every 12k-15k. Also include the transfer case if equipt.

You lucky. They might not have been contaminated. I suggest getting every thing up to date.

 

I'm not too concerned about the diff because the truck has never been offroad or driven in deep water.

About the trans though the 1-2 shift it revs up while shifting which i believe to be a band adjustment issue. I plan on taking care of the trans fluid soon and would want to do the bands at the same time b/c of some being in the pan.

Since I have the 2wd 5.2L I believe that I have the 44Re trans but I can only find torque specs on the 46Re by searching. Are they the same or do you know what they are? If they would be in the haynes manual I have that at home but if not where would I find them?