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2019-up 4.09 Rear Gear Swap
- Thread starter Scooter MGee
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TnWHTMARE
Well-Known Member
Just had mine installed. I know I am in the minority here but it just doesn't feel all that different to me. I admit I am a little disappointed. In 1st and 2nd at lower engine speeds, I just cant tell any difference or very little. It does seem like it gets through the gears quicker with more aggressive throttle. But overall I am just not as impressed as I had hoped. :( But I am glad it has for everyone else. I went 3:55 to 4.09. Dont mean to hi-jack the thread but I didn't want to start another one with negative input.
Sweetface
Well-Known Member
... as I've posted before on this subject , same here bud but it does pull much harder in 3rd at 3000 rpm than the 3.55s did for me.
DrZed
Well-Known Member
... I too, have been considering this. But going from a 3.73 to 4.09, and to hear a 3.55 owner not experience a significant difference, there will be even less for me.
Appreciate everybody's review of this.
Appreciate everybody's review of this.
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TnWHTMARE
Well-Known Member
I did see your post but not after I was already knee deep in it. I've only driven it to work once since the install so I'm sure I will appreciate it more in time. Just not the SOTP that I expected. Thank you for the input!!
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TnWHTMARE
Well-Known Member
Apparently some folks experience this differently so I don't want to paint a broad brush. Objectively speaking, Im sure it is faster. I guess folks just experience that to greater or lesser degrees. But knowing what I know now, If it were me and I had 3.73's, I would not spend the money. Just doesn't seem worth it, at least SOTP wise.
kz
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Even 255/40R19 (vs. stock 275/40R19) tire is noticeable and that's less of a gearing change than 4.09.
25.6" tall tire (315/30R18) which results in 4.06 ratio (compared to stock PP rear 275/40R19 tire and 3.73 actual gear in the dfiff) is very very noticeable. If someone can't see the difference, there is little hope...
TnWHTMARE
Well-Known Member
Yah, I've had Kooks LT's and the JLT and I wasn't impressed either way. That was with an A10. Im sure it pulled harder and made more up top but I dont spend alot of time up there and it "seemed" to have a more negative impact on lower RPM response/torque. I'm talking under 3k here.
I wouldn't undo the gears either.
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NGOT8R
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How bad is the whine with the 4.09s? I always attribute that to improper backlash setup. I’ve never done a rear gear instsll myself, but I did pay for one on a previously owned Fox Body and it howled like a werewolf. When I went back to the installer, he claimed that all 3.73 and up gearing would howl. I believe that to be some BS and think that the installer was just too lazy to disassemble and re-shim until the pattern was right.
TnWHTMARE
Well-Known Member
I would not agree with what he said. My 4.09's are quiet. MAYBE a slight bit around 45mph but thats it. Wouldn't know there was a different set in it.
kz
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If you're not reving up the engine, you won't notice it that much - try going up a little with rpm and there is no way you shouldn't notice it. Especially if you have E85 tune.I do agree with the "there is little hope.." part for me.
Scootsmcgreggor
Well-Known Member
There is a bit more noise the lower the ratio goes but it’s not a massive jump at least not with my 4.09 which my buddy set up meticulously. My 3.73 with a swapped pinion flange flange was wayyyyy worse.
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