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GuyMosher
Dodge Dakota
11/15/2001
11:54:42
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 Subject: 2002 4.7 have 6 Speed Auto?
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Is it true that the new 2002 4.7 Dakotas and Durangos have the same transmission as the 2002 Jeep Grand Cherokee? A 5 Speed auto with 2-2nd gears giving a total of 6 forward gear ratios-A 2nd .67 geared overdrive is the added result.
Is it also true that just a tranny computer flash will update a 2000+ Dakota to 6 gear ratios? Supposedly it's not an actual gear, but attains a newer .67 overdrive throught he use of clutches?
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Clevite 77
Dodge Dakota
11/15/2001
13:54:55
| RE: 2002 4.7 have 6 Speed Auto?
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Hey GuyMosher actually it's only a 5 spd auto I see where you may have thought it had a 6 spd, I think it has to do with using second gear to get the 2nd overdrive (I think??) but I know for sure it is a 5 spd,
regards to the trannys being the same that's how I took it, in fact I had asked the same thing but noone gave me an answer
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gUYmOSHER
Dodge Dakota
11/15/2001
14:25:35
| RE: 2002 4.7 have 6 Speed Auto?
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Well when I said 6 speed, I really mean a 5 speed with dual 2nd gears, for a total of 6 forward gears.
You only have access to 5 of the 6 gears. It only picks one of the 2nd gears depending on whether you're upshifting or downshifting.
The new JGC's have the same transmissions and now they supposedly still have the dual 2nd gears, but also a lower 2nd overdive gear. So it has a .75 AND a .67 overdrive gear. for a total of 6 forward gears, even if you'll only see 5 of them at a time.
I was under the impression hat the new 2002 Dakotas have the exact same transmissions as the 2002 Jeep Grand Cherokees
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NiPs
Dodge Dakota
11/15/2001
15:34:35
| RE: 2002 4.7 have 6 Speed Auto?
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I have to doubt this. You may be right in many ways and I am not certain as this is the first I have heard of this but my guess is that your either talking about the transmission from 2001(2000?) that has 2 2nd gears, for a total of 5 foward gears, so it's a 4spd with a 2nd 2nd gear making 5 foward gears total. I have heard nothing about a tans with 2 o/d's though.
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GuyMosher
Dodge Dakota
11/15/2001
16:26:54
| RE: 2002 4.7 have 6 Speed Auto?
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Check out...
http://www.jeep.com/grand_cherokee/full_specs/full_specs.pdf
It clearly describes 6 forward gears. And they have started using this in mid year 2001 models.
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robert
Dodge Dakota
11/15/2001
16:45:21
| RE: 2002 4.7 have 6 Speed Auto?
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It is a mis-print. The tranny is the 45-rfe. That is the multi-speed auto that came out in 2000. Jeep's website shows it when you build a vehicle.
The PDF is a mis-print.
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GuyMosher
Dodge Dakota
11/15/2001
17:05:29
| RE: 2002 4.7 have 6 Speed Auto?
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C'mon...that doesn't even sound realistic. A mid-print? So someone just accidentally put a .67 gear in the pdf file? I'm not buying into that...
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CW
GenIII
11/15/2001
19:36:19
|  RE: 2002 4.7 have 6 Speed Auto?
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The trans in the dakota and the trans in the jeep are the same only different computer programing. The one in the dakota is called the 45 RFE and the one in the jeep I think is called the 545 RFE. The 5 speed trans is a double overdrive unit but the second overdrive is so subtle that most people don't even notice that it has shifted. The difference between the two is only about 250 RPM at highway speed. The dealer can flash the TCM to make the dakota have the 5 speed. You may gain a little fuel milage but that is it, still has the alternate second gear for good highway passing.
2001 4.7 5sp RC 3.91 sport plus
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sandman
Dodge Dakota
11/15/2001
19:58:24
| RE: 2002 4.7 have 6 Speed Auto?
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Ford reprogramed their 4 spd A/Trans and got 5 forward gears. They are activateing 1 st and 4 th cluth packs to arive at a fith gear. I am sure that the same thing is being done with the Jeep. Your shift patern would look like this. 1,2,3,4, 4+1=5. I would like to know though if the added some friction plates and steels to the assembly? It seems like that extra shift would wear out the friction plate's/clutch's and steels alot quicker.
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robert
Dodge Dakota
11/15/2001
21:04:18
| RE: 2002 4.7 have 6 Speed Auto?
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Just go look on Jeep's website and start building a 2002 Grand Cherokee. It says the tranny is a 45RFE.
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joe
Dodge Dakota
11/17/2001
07:02:28
| RE: 2002 4.7 have 6 Speed Auto?
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I don't know for sure but I seem to remember Car and Driver describing this trans as a four speed with 2 choices for second gear. Thereby making it a "5" speed auto. perhaps that is way it is listed as a multispeed and not a true five speed btw, the only 6 speed auto I know of is B.M.W's unit.
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Kevin
Dodge Dakota
11/17/2001
13:17:20
| RE: 2002 4.7 have 6 Speed Auto?
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Message:
Heres what is going on... The new 4.7HO engine comes with the brand new 545 RFE. This tranny has 2 2nd gears and 2 overdrive gears. The 4.7 with the 45 RFE tranny has just 2 2nd gears and only one overdrive gear. These are two totally different trannys and is not reprogrammed in the TCM. Also the 4.7HO with the 545 RFE is currently only available in the Jeep GC. Those gear ratios are not a misprint. This info can be found on the net and at www.caranddrivernews.com
Kevin
00 4.7 auto 3.55LSD 4x4
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Kevin
Dodge Dakota
11/17/2001
13:26:42
| RE: 2002 4.7 have 6 Speed Auto?
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Message:
Here are the ratios...
545 rfe tranny
Gear Ratios
1st 3.00
2nd 1.67 - upshift; 1.50 kick-down
3rd 1.00
4th 0.75
5th 0.67
Axle 3.73
Overall Top Gear 2.80 - 4th; 2.50 - 5th
45 rfe
Gear Ratios
1st 3.00
2nd 1.67 - upshift; 1.50 kick-down
3rd 1.00
4th 0.75
Axle 3.73
Overall Top Gear 2.80 - 4th
Can be found at http://us.media.daimlerchrysler.com/special/2001carryover/gcherokee_specs_e.htm
Kevin
00 4.7 auto 3.55lsd 4x4
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CW
GenIII
11/17/2001
15:03:20
| RE: 2002 4.7 have 6 Speed Auto?
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The only diff between the two is TCM programming that is the beauty of it.
2001 4.7 5sp RC 3.91 sport plus
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sandman
Dodge Dakota
11/17/2001
23:25:29
| RE: 2002 4.7 have 6 Speed Auto?
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Message:
Hey guys just so you know, you can do this with gm's 4L80E with flash. If you rework the valve body you can also turn it into a 6 spd. The 45REF has alot of different options based on programing. They are useing this trany in the new Hemi sports car. They are just reprogaming it and they will probably use a different torque converter. It would be realy silly to have a different transmissions for the Grand Cherokee with the 4.7 then the Durango and Dakota and Ram with the same engine. THe BMW automatic is actualy made by GM/Adam Opel in Germany and it will be apearing in the new Catera/Cadilac CTS. Many luxury cars have 5 spd automatics. Give them a few years and you will see most car with 5 spd automatics and luxury car will all have 6 spd.
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Demon-Xanth
Dodge Dakota
11/18/2001
00:14:14
| RE: 2002 4.7 have 6 Speed Auto?
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Something funny, the 5 speed that was in the BMW 3 series was a GM unit :)
Really funny, at one time the 4 speed in the Jaguar (Ford owned) XJ-r was a GM unit as well :D
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SuperDak
Dodge Dakota
11/18/2001
00:42:12
| RE: 2002 4.7 have 6 Speed Auto?
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whats the advantage of 5spd over 4spd in an auto?
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joe
Dodge Dakota
11/18/2001
06:40:10
| RE: 2002 4.7 have 6 Speed Auto?
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Super dak- The adavantage is better fuel economy. lower rpm in overdrive.
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NiPs
Dodge Dakota
11/18/2001
12:16:18
| RE: 2002 4.7 have 6 Speed Auto?
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Well ... One could set up the gears for a 5sp auto the same as a 5spd auto making the difference between a 5spd and a auto minimal. However this won't happen most will make two over drive gears or one at 1 and one at .70 or so.
The best gearing in my opinion would be like ...
1st 3.10
2nd 1.70 - w/2nd maybe a 1.5 or so
3rd 1.15
4th 0.95
5th 0.60
This would be great and once at highway speed A) you'll have more power to get to high speeds if one wanted too, and good fuel milage.
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Ian
Dodge Dakota
JOIN HERE
2/11/2003
17:05:00
| RE: 2002 4.7 have 6 Speed Auto?
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What do you think it'll run me to have the dealership flash my tcm to convert it over to the 5 speed?
02' 4.7 QC Auto
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Ian
Dodge Dakota
JOIN HERE
2/11/2003
17:43:15
| RE: 2002 4.7 have 6 Speed Auto?
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bump
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Demon Dakota
DakotaEnthusiast
2/11/2003
17:57:59
| RE: 2002 4.7 have 6 Speed Auto?
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Message:
Did you notice how old this post was when you replied to it? Just call a local dealer and ask what they charge. No need for us to speculate when they can truly answer.
K&N Drop in AF
True Dual exhaust and removed third cat
HO Cams & HO Intake
Modified TB
Autolite 3923 Plugs
TPS @ .76 VDC
IAT Adjuster Mod
14.52@94.2 MPH at Silver Dollar Raceway
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blueballs
Dodge Dakota
JOIN HERE
2/11/2003
21:00:08
| RE: 2002 4.7 have 6 Speed Auto?
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If the converter could be lock mid gear it would divide the shift. Ford does this in some of there flag ship cars. Make it a close ratio. Really cool to drive and is always in its power band.
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Ian
Dodge Dakota
JOIN HERE
2/11/2003
21:10:19
| RE: 2002 4.7 have 6 Speed Auto?
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Demon...I was busy all day with access to the internet but not to a phone I was hoping someone had done this already and could tell me off the top of their head, but I catch your drift. I can't believe the incompetence of some of these service technicians, I talked to two of them today over the phone, one at a Los Angeles dealership and one in Orange county, the first one told me they have to plug in my computer to their scanning tool to see if it is compatabile with the 5-speed tcm programming and the other guy did not know what he was talking about he tried to say there is no way to turn 4-speed into a 5-speed, that the 02 and 03 transmissions are physically different trannies, i tried to explain it is electronically controlled and thus reprogramming can change the amount of shifts but he kept arguing with me. I'm but a humble novice when it comes to cars but how does Dodge have these guys servicing their vehicles and they don't know jack sh*t!
P.S.
the one guy who sort of knew what was up said it would run me anywhere from $70-$140, depending on if any parts were needed, no parts are needed though just the computer scanner to program the knew tcm code right?
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Manny guy
Dodge Dakota
JOIN HERE
2/12/2003
09:52:00
|  RE: 2002 4.7 have 6 Speed Auto?
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Some people have a REAL 5spd! Not this, slip some, maybe not, downshift to a different 2nd gear, etc. crapola
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STS
Dodge Dakota
JOIN HERE
2/13/2003
17:39:12
|  RE: 2002 4.7 have 6 Speed Auto?
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You would be talking about the 5-45 RFE tranny?
Its's already in the Durangos and now in the Dakotas. Also Its optional in the Ram. This transmission is mated to the 348 half Hemi and also the H.O 287 P.T (powertech)
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