Has anyone every switched out the gear ratios on an 05 srt crossfire?

 

to 3.27... working on 3.48 but not there yet...

 

do a search,,,,3.07 3.27
I think you posted in the new member introduction thread .. maybe this should be moved to the differential section.

 

I have been using 3.69 for about a year. Fuel economy dumped but like adding
100HP

 

Tell us more about your 3.69 gear. Squirrel Crusher

 

this link was in 2004 then nothing til 2007 and never a word about the 3.69 gears so if this is the same person with a new handle ,, or not we would like to know about the 3.9,, is it a bolt in diff only or do you have to change the sub frame? https://www.crossfireforum.org/forum...ight=3.69+gear
I have found a 3.73 gear set in a diff but the sub frame has to be replaced and some welding is needed to complete the upgrade,,, we want a bolt in as I have the 3.46 as a bolt in, doubleloader we wait your reply thanks for any and all info on this subject. jim

 

I made an error. You are correct the ratio is 3.69. Ratios are available from 3.69 to the mid 2.0's.
Several years ago I spent six months looking for differentials that would just bolt into the crossfire.
There was a common denominator for differentials that just bolted or directly replaced our differential.
I saved the info of course, but I have forgotten what I did with it. I will look after the first.

When I bought the 3.69 I also purchased an 3.67 and I have advertised it for sale but no body wants to
pay. They are not cheap but considering there is no need for structural mods it is cheap.

Tell me what ratio you are looking for and I will see what I can find.

 

I still got wrong.

3.70 is the ratio. There is a 3.45 available. Bolts up.

 

HEY DoubleLoader. I'm a little slow understanding sometimes. Are you saying there's a 3.70 and 3.45 gear set avaliable that will bolt directly into our factory Crossfire rear housing? If so,the gears should also bolt up directly to a WaveTrax LSD thats made for out cars? Or were there machining modifications required? Or are we talking about slipping a different model cars rear end up under our car? I'm in hopes you have made a unique discovery. Thanks..Squirrel Crusher

 

Wondering the same thing that would be awesome if you could let us know

 

there are machining and or a spacer to be made to fit any gear set into our car other than the 307 or the 327,, then you have to set it up,backlash and such. at the time double had his rear done,,,I think it is out of a 190 it is not strong enough for the crossfire,, as you know i have done a lot of research on diff, well none without Rudy and Rob. when i say i can build a 3.46 for you what i am saying is Rudy and I will build you a diff. we tried the 190 about 14 months ago,, with my V8 i blew it up in lass than 1 mile ,,the second burn out it exploded and there are other gear sets that will fit but i and Rudy are only using ones that we know should work and last 3 to 400,000 miles. hope this helps everyone understand the diff for the crossfire.

 

Reminds me of the story of the IBM repairman back in the dark ages who comes out to fix a mainframe.

Dissapears inside, they hear a "clank" and all the lights come on and tape (9 track) reels start whirring and he comes out holding a small hammer.

Presents a bill for $ 5,000.00. Bean counter says he needs an itemized bill so the guy with the hammer writes down:
Hammer strike: $5.00
Knowing where to strike hammer:: $4,995.00

 

There are differentials available that bolt up to the crossfire with no mods. I have two of them and they
work just fine with no failure so far. I did send the differential to Wavetrac for installation as it
requireed a spacer they had.

Look, I am not trying to sell anything. If you have a better way that is what I would want you to
pursue.

 

yes i remember a little over year ago don't remember exactly when i made two spacers for unatrax so the wave trac would fit in a rear they were doing ,,now i know it was yours. there was some machining to do that rear that you may not have known about, Devin and I along with Rudy Rob and Allen have been with Devin from the initial wavetrac. thanks to you we now have a few gear sets we can work with, jim
ps Devin is no longer working at unatrax.

 

Sad to hear Devin no longer works for Unatrax. Squirrel Crusher

 

Everyone assumes that Mercedes only used the SLK/Crossfire differential in that platform, but it was
used in many other platforms over the years. Those platforms had many other ratios. So the hunt is
for those differentials.
If I can find one (3.45) we could then use the part number of the ring and pinion and buy that
from mercedes.

 

Jim is right. Durability of the gears is a huge concern. I've had a bit of a problem keeping pinion gear teeth on the pinion gear.

Where did they go?
ForumRunner_20160103_182322.png

Oh, there they are.
ForumRunner_20160103_182302.png

This was my 2nd differential, WITH a Wavetrac LSD. My original diff died when one of the spider gears blew up.

For diff #3 Unitrax hardened and finished a new gear set for me. Wavetrac was awesome and rebuilt/upgraded the LSD for a reasonable price even though it was not the LSD that failed.

 

that is a great idea let us know, more. thanks jim