2nd Gen Non-Engine/Transmission Anyone make higher diff gears for 2nd gens?

[CanadianCarGuy]

I have been wondering if there is a company that makes higher gears than what comes stock in our front and rear differentials? I think my truck has 3. 55's, but I would like higher gears, way higher gears! I would like at least a 25% reduction in RPM's at highway speeds. Then I could actually drive with the overdrive off at 50mph.

 

[Nate]

I believe it's 3. 55-7. 17. I could be wrong though

 

[steved]

I talked to a guy one time and said anything from 2. 8x-7. 17 was available. But I believe you would need to switch the front to a D61 to be able to fit anything lower than 3. 55.



steved

 

[Joe G.]

What is the problem in running at 50 with OD off? I do that all the time. Only use OD at higher speeds than 50.

 

[Dieselram]

I don;t understand why you would want gears any lower than a 3. 55 unless you plan on driving 150 mph all the time? at crusing speed 70-80 you would only be turning between 1300-1600 rpms and it would be constantly lugging the motor to keep it going, Much less leaving red lights it would put more strain on the auto transmission just to get the truck rolling? I'm curious as to why you want a lower gear?

 

[NoSeeUm]

What RPM you looking for? Why is your goal driving with OD off? Just curiousity on my part.



I have 285 tires and that is about 1600 RPM at 60 MPH.



Jim

 

[PRattenbury]

If you can't find gears with a lower numeric ratio, you could get bigger tires. I have 3. 55's. When I put on the bigger tires, it changed things quite a bit in the direction you want to go. But I don't like it, so now I'm going to find some 4. 10's.

 

[steved]

On my 99 I ran a 255x85R16 that was a true 33. 5 inch tall tire, but it was only like 7 inches wide... awesome snow tire.



That would definately be cheaper than trying to regear both ends...



steved

 

[onestackdram]

I would reccommend getting taller tires, it would be WAY cheaper than regearing. I want to go to a higher gear but I have 4:10's and can't go to a taller tire with my dually and the fact that to get where I want to be with RPM's i would have to have something like 4 FOOT tires. . lol, it sooooo much cheaper to buy tires than a r&p for both ends and depending on how far you go buying a carrier for both ends, and then you have to buy the shim pack and basically an overhaul kit for both ends.

 

[Nate]

I run 4. 10s and 35s. 75mph (speed limit) is a tad over 2000rpm.

 

[CanadianCarGuy]

At 60mph my truck is revving 1750RPM. The reason I want higher gears is so I can go way faster! I would like to hit the salt flats or silver state cup classic with it one year.

I always wanted to have a cummins that went over 150mph. Maybe I am just a dork, but I sure like going fast in big trucks, my poor cars never get driven anymore!

 

[Joe G.]

Have you considered an after market OD?

 

[CanadianCarGuy]

Yes, but DTT transmission tech guy advised against it. Everyone I've talked to who had one didn't like em, so I figured diff gears was the best way to go.

 

[MEby]

ask around to see how much a gv overdrive would net you in terms of rpms.

 

[CanadianCarGuy]

The problem with gearvendors is that my truck is 4WD and their overdrive for my truck would over $6,000. I have contacted them a couple times and never get a response. The gear vendors overdrive is a 20% drop in RPM's.

 

[Philip]

But I believe you would need to switch the front to a D61 to be able to fit anything lower than 3. 55.

The D61 is a right side pumpkin also. He needs one for a left side. As far as I know the D61 was never made in a left side version. Plus they are very hard to find even in right hand.



The D71 rear is even harder to find. I went threw that a few years ago when I found my rear axle bent.



The carriers from a 61 or 71 will not fit work in a standard 60 or 70 housing. The housing are different.

 

[SnoKing]

The problem with gearvendors is that my truck is 4WD and their overdrive for my truck would over $6,000. I have contacted them a couple times and never get a response. The gear vendors overdrive is a 20% drop in RPM's.

You only do the rear axle and use it only in 2 wheel drive! SNOKING