Diesel Place banner
1 - 16 of 16 Posts

·
Registered
Joined
·
50 Posts
Discussion Starter · #1 ·
On one of the fuel mileage posts, somebody suggested that the gentleman who started the thread should switch to 3.55 gears. Is this available anywhere - site? I ask because I have a dually with 4.10s. I was looking at doing a swap because most of my tow loads are under 5K, but the only gears I could find were 3.73s and 3.42s. The difference between 4.10 and 3.73 isn't enough to justify the cost and I worry about going to 3.42s with my truck because I don't want it to be a 'dog' when towing. The 3.55 or 3.6X may be a good compromise, but I haven't seen it offered anywhere. Anybody know of a site that offers an 'in-between' gear?
 

·
Registered
Joined
·
8,014 Posts
I don't recall seeing a 3:55 for a 6.5 definately not the norm maybe check with a gear mfg like richmond gear, or Randy's ring and pinion for advise search the web should be easy to find
 

·
Registered
Joined
·
3,752 Posts

·
Registered
Joined
·
1,954 Posts
I believe they are available aftermarket. Randy's is a good choice.
 

·
Registered
Joined
·
1 Posts
Hey im new to this site and i was wondering what would a stock 6.5 ext. cab shotbox have in it for gears???

Thanks Jaymes
 

·
Registered
Joined
·
2,006 Posts
Hey JD, Please fill out your signature so we know what truck you got and are asking questions about. If it's 1/2 ton it could be about anything and hard to tell without your production codes. 3/4 ton again depends on LD or HD, the choices are a little narrower but still have a few it could be. Again the production code would be helpful. And I don't think I've ever seen a 1 ton with anything but 4:10, oh course someone else may have.

Thanks for helping us help you

Here's a thread you might be interested in http://www.dieselplace.com/forum/showthread.php?p=496017#post496017
 

·
Registered
Joined
·
8,014 Posts
JD welcome to the site, hit up the RPO code list in the FAQ yours should be there. Check out the links in my signature good way to start off here in the 6.5 forum, read up 90% of the new to 6.5 stuff is in there.

Chris I just got back from road trip on my way out again soon, I glanced at the list, it made it's way to the moderators forum, I'm not sure how external linking will be solved if I can link it I will.

But for now there is too much in that list for this moderator to add to the list manually you can take that one on if you like; thing about the FAQs and why I link threads is so the 6.5 community as a group has the opportunity to assist, if a thread is locked from inactivity & auto lock down PM me or one of the other moderators to open it back up, I'd concentrate on most requested codes unless you have a lot of time to add them all. here is the link and opened up have at em
http://dieselplace.com/forum/showthread.php?t=9676
 

·
Registered
Joined
·
7,134 Posts
3.42 versus a 3.55 is a very small difference. I believe GM only used the 3.42 though for it's axles.
 

·
Registered
Joined
·
6 Posts
3.55 for what rear axle? 14 bolt? only 3.42 and 3.55 available in yukon or the value line. Motive gear same thing.

3.42 is a very small difference though. If you tow semi frequently, but are still looking for better fuel economy. I'd lean more towards 3.73.
 

·
Registered
Joined
·
8,014 Posts
For the 6.5 that is pretty uncommon 3:42, 3:73, & 4:10 are what I've seen listed call Randy's to see if they recommend it for the 6.5 I don't know one way or other but they do many & should have some input http://www.ring-pinion.com/
since it's so odd ball for the 6.5 I think availabilty might have an effect on price or even durability maybe, call them & find out post back what you find
 

·
Registered
Joined
·
3,752 Posts
Thanks TD - the thread was locked before. I just put in the URL to the pdf file so that guys can look up their own RPOs.
 

·
Registered
Joined
·
50 Posts
Discussion Starter · #13 ·
No 3.55 available for the 14 bolt according to Randy's. Recommended not going below the 3.73 with the dually. Not sure I gain enough to justify the cost - but I may do it later when I get some of my other projects wrapped up. From somebody who has done this conversion before - can you give me an idea on a scale of 1-10 of the difficulty factor - 1 being easy and 10 being don't do it - pay somebody. Thanks.
 

·
Registered
Joined
·
7,498 Posts
Factory gear would be a whole lot better than any aftermarket gear as far as durability and noise.
 

·
Registered
Joined
·
6 Posts
Mechanically inclined and have patience it's an easy swap. Need the right tools though. Shop press, bearing puller, inch pound torque wrench, and dial indicator with magnetic base are the biggest. Yukon Gears with install kit averages $350.
 

·
Registered
Joined
·
1,224 Posts
On one of the fuel mileage posts, somebody suggested that the gentleman who started the thread should switch to 3.55 gears. Is this available anywhere - site? I ask because I have a dually with 4.10s. I was looking at doing a swap because most of my tow loads are under 5K, but the only gears I could find were 3.73s and 3.42s. The difference between 4.10 and 3.73 isn't enough to justify the cost and I worry about going to 3.42s with my truck because I don't want it to be a 'dog' when towing. The 3.55 or 3.6X may be a good compromise, but I haven't seen it offered anywhere. Anybody know of a site that offers an 'in-between' gear?
Just a word of advice - I'd strongly encourage you that if you change the ratio be sure to scratch out the RPO code in the glove box or put a permanent note someplace so that the next guy that buys this truck knows he's got highway gears and not towing gears. If it was me and I bought one thinking it was 4.10 and it ended up being 3.55, 3.42 or whatever, I'd be ticked off in a big way.

SnowDrift
 
1 - 16 of 16 Posts
Top