RPM compare to speed?
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RPM compare to speed?
Well. Tryin to decide what tranny im going to look for. auto 5 or 6spd. its gonna be a used 03 probably so the chances of finding a 48re are pry slim. But my 47 in my 99 is runnin 150k with no problems. So thats not REALLY a consern here
What im lookin for is the RPM and cruising speeds. my 99 runs me around 70mph at 2000 rpm. Nets me about 21 or so in mileage
What do the new trannys run? Since the rear is a lil shorter?
I dont mind the shifting i dont think haha. Care about reliablity but in the long run the current auto is lastin for ever and this one will pry be bombed down the road anyway
Any ideas?
What im lookin for is the RPM and cruising speeds. my 99 runs me around 70mph at 2000 rpm. Nets me about 21 or so in mileage
What do the new trannys run? Since the rear is a lil shorter?
I dont mind the shifting i dont think haha. Care about reliablity but in the long run the current auto is lastin for ever and this one will pry be bombed down the road anyway
Any ideas?
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It is my understanding that the 47RE and the 48RE have the same gear ratios
2.45, 1.45, 1.0 and OD 0.69
Remember the ultimate RPM vrs speed also depends on your diff ratio and tire size.
Hope this helps
cheers f
2.45, 1.45, 1.0 and OD 0.69
Remember the ultimate RPM vrs speed also depends on your diff ratio and tire size.
Hope this helps
cheers f
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sounds about right then. Guy I was talkin too. Hes takin the Big Rig driving class where I Take my Diesel Tech. He said he ran about 2200 in 6th with his so im like Thanks for hte info guys
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Awesome Good info. Ive got it knocked down to 2 now. Either the Auto or the 6spd. Ive tested all. Over all i think the auto might win out. The 5 speed was a lot of shifting and no fun. The 6spd was a lot of shifting but, you got that extra brunt there. One thing i found myself doing was jumpin from 2 to 4 to 5 with the 5 spd. And from 2 4 6 with the 6 spd which made it a lil better. Another thing i found with these trucks that isnt true with the lil car standards in on hills. I hated trying to do that but with these i can put her in one and leave a foot on the brake and another on the clutch and she wont die! I love that. Good stuff there. Just can decide. Mileages are seeming to be the same. But theres a lot more 6 spd used 3rd gens out there than autos!. I hate complications
Oh yeah. Whats everyone think of that shift pattern? Think it s hard on the trannys?
Oh yeah. Whats everyone think of that shift pattern? Think it s hard on the trannys?
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According to the worksheet,my speedo must be off. I actually see 70 at a cooter hair below 2100 rpm. w/245/75/16 and 3.55 gear. Southerners...gotta luv us.
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At 70 MPH I'm right at 2000 RPM with the 6sp. manual. I like the manual for towing the 5er, and have the Jacobs Ebrake which I enjoy the benefits of very much. If I'm running empty highway at 1950 RPM (68 MPH) I will get a manually calculated 18.5 - 19.0 MPG; around town (most of my driving) averages out at 16.5 to 17.3 depending on how many start/stops I have to make. I'm probably the odd one out here, but I use all six gears, even running empty.
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Try using the manfactures revs per mile instead of the generic tire size. When I plug in 601 revs per mile for the BFG 315's as opposed to 315X70-17 the difference is a whopping 2 MPH! Play with the numbers and have fun!!
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Jerry R
RE: Try this, it's very good.
http://www.klenger.net/dodge/genera...-calculator.xls
The spreadsheet looks great. The nos jive with my calculations except yours are variable. I have the 47RE and 48RE numbers in KM/H if you are interested. Of course the spreadsheet could accomadate the Ks or Ms .
Good show
Frank B
RE: Try this, it's very good.
http://www.klenger.net/dodge/genera...-calculator.xls
The spreadsheet looks great. The nos jive with my calculations except yours are variable. I have the 47RE and 48RE numbers in KM/H if you are interested. Of course the spreadsheet could accomadate the Ks or Ms .
Good show
Frank B
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