Noticed a few threads regarding fuel octane so got out the manual. 87 octane OK for 4.7 & 5.2 but in BOLD 5.9 RT must use 91 Octane. We've been running 87 since we got it and didn't notice any problems except MPG (who doesn't, if I wanted fuel economy I wouldn't have purchased any Durango). I tried some 91 and realy can't say that there is any difference.

 

We found some differences on the R/T models such as fuel Octane and transmission final drive ratios. I think these differences are based on the geographical location you live in.

My R/T did not like the unleaded fuel and will never fuel up again with regular unlead. Gas mileage dropped just a tiny bit, but the big noticable difference is power loss and engine knocking/pinging when you try to put it under power.

 

Thanks for the reply. I should have mentioned that the ratio is 3.92 and that I live in Southern Ontario( which is actually about the same latitude as N. California), although I can't believe that they would build D's differetly based on where they were going to be delivered.

 

Yeah, we had this debate a while back. Some Durango R/T's do not use Premium and some do. "Last of the R/T's", his 03 R/T does not require premium if I remember that right. Also, his RPM reading at 70 mph is way off from my RPM reading at 70 mph.

Last of the R/T's 2003 R/T - 70 mph at 2000 rpm's. Does not require premium. His manual does not state premium required.

My 2000 R/T - 70 mph at 2250 rpm's. Requires Premium. My manual states "PREMIUM REQUIRED AT 91 min OCTANE"

Both of us has 3:92 gear ratios, same size tires. I assume there may be a difference on the final drive gear in the tranny?

Alot of other R/T users also have either Last of R/T's settings or my R/T's settings. So I must guess it may be geographical. My reasoning for this conclusion is some areas like Denver, the Octane rating there is much lower, problaby because of altitude. East coast regions may differ from west coast because of extreme climate differences such as east being extremely cold during the winter seasons..

 

FWIW, you can go read the other for my answer since you posted this in two different threads or look here...

The 91 octane retards the spark pinging from the different program in the PCM that the RT has over the SLT/SLT+. As the years went on, the RT no longer had a different PCM program thus the dropping of the requirement. Your '01 = 91 octane.

IndyD

 

If this is true, then the Power output of the 03 R/T is the same as the 03 SLT/SLT+?

 

That is correct. After '00, the Durango R/T was more marketing that anything. Note the LACK of differentiation on the HP indications from year to year on these link:
http://auto.consumerguide.com/Auto/U...arreviewspecs/

On these, you will see indication of 10HP difference between the SLT and the R/T. You can get 10HP by running 91 octane all the time (as is recommend for the tune on some of the R/T PCMs) and the use of a better air filter... LOL:
http://autos.msn.com/research/vip/Sp...ango&trimid=-1
http://www.internetautoguide.com/car...ngo/index.html

Suspension tweaks, different seats, different rims... that's about all that's different on the R/T D after '00. They both provide excellent platforms for modifications. I prefer the refinement on my wood grain interior, tufted leather door inserts and other SLT+ features that the R/T lacked. I can always add HP and improve the ride characteristics... which I have. My current '00 SLT+ will smoke any stocker R/T any day of the week.

HTE (educate)

IndyDurango

 

My only qwerk on the R/T is the Full time drive system. I don't really need it, I just prefer part time drive system. Man, I miss the tiring peeling when you have an itch for it. I'd bet my MPG may go up a little bit just driving in 2WD mode vs AWD mode. It would be nice to have a switch to enable 2WD or AWD mode.

 

Ditto. We both have the same drive train then. 4, 4hi and 4 low. No 2-wheel, ever.

Do you have the 3.92s withthe limited slip?

While I'd love to 'burn out' everytime I think of that, I remind myself that I am hooked up and headed down the track while the other guy is still spinning his tires or feathering the gas pedal.

BTW, On the '00 it is a FT4x4, not AWD. AWD started in '01. Similar?... yes, Very similar?... yes, Very very similar... yes again. Exact... no.

IndyD

 

Then exactly what is the difference between Full Time 4x4 vs AWD? I thought they were the same, just different wording.

Yes, I have the limited slip 3:92 gears.