changing rear end and or gears

rdbishop · August 19, 2009, 05:28:48 PM

Hey guys,

My brother-in-law has an 01 Eagle and wants to go to 336 gears. Does anyone know what kind of rear end is in there and what standard gears would be?

Thanks,

Richard

luvrbus · August 19, 2009, 07:15:41 PM

Richard, it is a Rockwell with 3.73 gear the housing will accept up to 3.33 gear.
The 01 is just a truck rear flipped over.
If he has a 8v71 with a manual 4 speed a 3.36 would be a poor choice for him but if he has a 740 auto they make a wicked 3rd gear with the 3.33,3.36 and 3.38 rear gear. good luck

Dreamscape · August 19, 2009, 07:25:18 PM

Clifford, In my manual it says Ratio 37/10, what does that mean? It does not mention anything like you posted. It also says "All up to #7443". I'm assuming all 01's and ending with ours #7443.

I'm going to write the information in my manual since it seems to be what is needed.

Sorry for the hijack Richard.

Paul

rdbishop · August 19, 2009, 07:27:18 PM

Thanks Clifford,

He has a 8v71 with turbo and a 5 speed auto. He's trying to lower his rpm and help his milage. I'll check around San Antonio tomorrow and see what I can find.

Thanks Again,

Richard

NJT 5573 · August 19, 2009, 07:30:02 PM

If its Rockwell, maybe it's a SQHD. The year is about right. The most popular truck diff for 20 years. If it is, they are pretty easy to find although it may take some looking to find that ratio. Rebuilt/exchange though its only around $800.

37 teeth on the ring gear and 10 on the pinion gives you the ratio. (3.70)

luvrbus · August 19, 2009, 07:32:54 PM

Paul, 37/10 is a 3.70 ratio if you count it it will be a 3.73

good luck

rdbishop · August 19, 2009, 07:33:04 PM

Hi Paul,

Come on in anytime. I think that means you have 3.70 gears.

Richard

Dreamscape · August 19, 2009, 07:34:32 PM

Hi Richard,

Yip, now it all makes sense. That is one area I don't have much knowledge on and this helps.

Paul

rdbishop · August 19, 2009, 07:36:22 PM

OK Clifford,

Which would be the best ratio?

Richard

David Anderson · August 20, 2009, 09:58:15 AM

Richard,

I have 3:36 gears on my 10, but attached to a Voith 4 speed auto. At 70mph I turn 1950rpms. At 80 I turn 2100rpms. I like the the setup, but tough to get rolling if there is a hole the tire is in or steep hills. I'm just down the road from you in Pleasanton.

David

luvrbus · August 20, 2009, 10:22:02 AM

Richard, if you find the 3.36 go for it makes a good combo with the Allison and with his 8v71T it will handle it ok a 3.38 will work good also.
The 3.33 gear are about impossible to find.
If someone wants to sale you one from a 05,10 ,15 or 20 don't buy it will not work.
To answer your question the 3.36 would be my choice but I would love to have a 3.33 for my 05

good luck

DaveG · August 20, 2009, 04:59:06 PM

So smart guys, which model Rockwell rear end/housing is in an Eagle? SQHD is a tandem set-up.

luvrbus · August 20, 2009, 05:51:58 PM

I never said it was a SQHD but try this and see if it helps you R162

Good Luck

rdbishop · August 20, 2009, 06:32:04 PM

can anyone tell me where to find a speed calculator?

Richard

NJT 5573 · August 20, 2009, 07:11:46 PM

Think Crown used the rear SQHD for a single drive unit. Know they used SQHD's in the tandem buses. Doubt you would be that lucky though. Likely has the heavier unit used on single axle trucks from the 50's and 60's. Think that was the R 180. Not all housings are the same either. You should check with a gear shop and see what they can build for you because I don't like your chances of finding a used drop in with a gear that high.