3.5:1 Rear differential

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Pjackb
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3.5:1 Rear differential

Post by Pjackb »

I've seen mentioned a few times a 3.5:1 rear differential mostly by Mike young but I can't find any information on what car it came from and what not.
Anybody knows ?
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SLOroadster
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Re: 3.5:1 Rear differential

Post by SLOroadster »

I believe the ring and pinion come from a truck. The housing needs some modification as well.

I like the way a 3.5 drives more than a 3.7. It makes each gear really long, but at least it doesn't feel awkward like a 3.7.

Will
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spl310
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Re: 3.5:1 Rear differential

Post by spl310 »

Gear ratios and part numbers.

3.364 38100-P0806
3.545 39/11 38100-P0706,38100-V7700
3.700 37/10 38100-77700,38100-A3800,38100-P0606/38100-P0607,38100-V7600
3.889 35/9 38100-61000,38100-A5300,38100-25600
38100-P0501/38100-P0506,38100-V7500
3.900 39/10 Not available (3.889 is quieter)
4.111 37/9 38100-61001,38100-P0306,38100-V7300
4.375 35/8 38100-37800/38100-22501/38100-23500,38100-26000
38100-B3300,38100-B5500,38100-P0206
4.625 37/8 38100-36800/38100-22600,38100-22901,38100-77500,38100-P0106,38100-C6200
4.875 39/8 38100-14901/38100-20600,38100-20659,38100-Y4006
5.125 41/8 38100-37000
5.143 41/8 [5.125] 38100-08700,38100-37000,38100-B4003
5.429 38100-T3003
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Pjackb
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Re: 3.5:1 Rear differential

Post by Pjackb »

Thanks
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funkaholik
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Re: 3.5:1 Rear differential

Post by funkaholik »

Mike mentioned this to me, as well. If I recall correctly, he said that the 3.5 center section from 1981-88 Maxima wagons fits right into our roadster diff housing.
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Re: 3.5:1 Rear differential

Post by redroadster »

Put me down for a couple 3.36 s ....ha ha ha
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Re: 3.5:1 Rear differential

Post by Pjackb »

redroadster wrote: Fri Oct 08, 2021 7:14 am Put me down for a couple 3.36 s ....ha ha ha
Good luck finding one
funkaholik wrote: Fri Oct 08, 2021 12:45 am Mike mentioned this to me, as well. If I recall correctly, he said that the 3.5 center section from 1981-88 Maxima wagons fits right into our roadster diff housing.
77-84 Maxima Wagon and certain other imports , What he did not say is that's its almost impossible to find now :lol:
to give you and idea I just searched for a couple months to find a same generation Maxima Sedan 4:11 R180 differential for my Z and that was ultra hard to find
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Re: 3.5:1 Rear differential

Post by redroadster »

I'm not doubting you on they were made , but so rare
81thru 84 were rwd 85 up Fwd same ring & pinion?
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rwmann
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Re: 3.5:1 Rear differential

Post by rwmann »

And here I thought a 5.13 was the hot setup...
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FergO2k
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Re: 3.5:1 Rear differential

Post by FergO2k »

I think I have said it before, but I have an Excel spreadsheet (from Vic Laury, miss ya buddy) with graphs and the individual gear ratio listings for 25 different Nissan transmissions. Can send it along if anyone wants.

Also a separate file with Rpm vs Speed that you can enter your own tire/wheel sizes to determine accurate speed. (though it does need a bit of a factor, as it over estimates. I don't think it takes into account a tire not being perfectly round on the bottom, so effective radius is a bit smaller)

How do I know t is off? Most hybrids have a 1" or larger speed display on their dash, so when dark I just drive up next to them on the freeway and look in. (creepy, I know!)
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spl310
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Re: 3.5:1 Rear differential

Post by spl310 »

I'd like to see that spreadsheet!
"Wow, a Roadster!" Stuart Little

1967.5 2000
1967.5 2000
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1964 1500
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1968 chassis
2000 Durango
1995 F350 Powerstroke!
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FergO2k
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Re: 3.5:1 Rear differential

Post by FergO2k »

Let's se if this works.
RDSTR_Trans_Calc.xls
gear_ratio_rpm.xls
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Fergus O
69 2L, SUs (driver, not susceptible to polish)
02 Tacoma 4 door (sold at 300k miles!)
2017 Honda Ridgeline (2021 purchase)
Los Alamitos, CA