axle & transmission ID

[BCronk]

axle & transmission ID help please

I have an 89 ctd 2wd auto. I was told earlier that my gear ratio would be 3. 07, well I had the diff cover off and it is a 3. 54 with posi. The guy I got the truck from said the rear end had been rebuilt. Do you think the rear end was actually swapped with someting newer? I have heard that the dana 70 with 3. 07s was unique and the only gears that would fit are the 3. 07s. Here is the info I have from the diff.



ON the diff cover

dana

248 15 2

1 12 2

rev v

07-06-98 (is this a build date? if so my 01 has a 96 axle, old parts on new truck? I did buy the 01 new)



under the diff cover on the gasket surface

OD

np241c

I guess this info is only relevant if diff cover came with this axle. Can anyone interprit these numbers? Aso what is the gear looking thing that is sndwiched between the ring gear and carrier?

next question. How do I ID the transmission if it has been swapped? the only numbers I could get from it are cav 1a go8. Thanks for any help.

 

[BCronk]

come on guys share your knowledge with the new guy (me). I know some one here knows the answers to my questions. anyway I am just posting to my own thread so it doesn't get buried and no sees it again. thanks for any help

 

[Paychk]

If you want to ID the rear axle go here:



http://www2.dana.com/expert/wc.dll?cvsp~deabill~2~



What you need to find stamped on the axle tubes are the B. O. M. (bill of material) number, it'll look like this XXXXXX-X. The numbers you provided would only have meaning to the right Dodge parts man, he may be able to de-code them.



The ring is called the tone ring it provides the signal for the ABS system.



3. 07's are unique to the housing they came in.



As far as the trans go I'll have to do some digging on that, may be able to get it for you tomorrow.

 

[pepecat]

transmission ident

it should be fairly easy to figure out what transmission u have. First of all, count the shifts, if it up shifts 3 times, it's an a518 3spd w/ od, if it only upshifts twice, it's the original 3spd 727... Other things are does it have a tps or a kickdown cable? What about a lock up converter??? Hmmm? Well if you can't tell... what is your top spd?? If it is really low than you prolly still have the original 727 3spd. Why not call and ask the owner about the full history as it looks like someone did some mods, possibly in addition to drivetrain, possibly fueling.

 

[pepecat]

FYI Just looked under my truck while changing the oil and noticed the same numbers you posted on the bell housing of the auto transmission. I have a 727.

Nick

 

[BCronk]

OK guys now I am realy confused about my rear axle. I went to the dana sight and put in my bill of materials number (605311-1), and it turned up 3. 07 with standard differentual. I counted the teeth on the ring & pinion 46/13 this comes out to 3. 538... so how is it possible to have 3. 54s in the 3. 07 housing?

 

[pepecat]

Wow

Well if it is, you have something that was previously considered impossible, so investigate and let us 3. 07 owners know the good news

 

[HFletcher]

The case accomodating the 3. 07 gears is unique. However, you can put 3. 54 gears into a 3. 07 case by using a spacer. I don't recall who makes that spacer, but have that info on another computer. I'll dig it out if no one else chimes in with that info.

 

[Philip]

I am not sure of the spacer part for using a bigger rear gear.



This is the only thread on the TDR I know of where a member installed another gear in a 3:07 housing.



https://www.turbodieselregister.com/forums/showthread.php?t=68679&highlight=in+here+Philip



If you guy's knew how long it took me to find this old post. :-laf :-laf



If you don't belive me do a search on my user name.

 

[mysteryman]

Putting a spacer between the ring gear and the differential is an old trick that has been used for years to put lower ratio gears in a high ratio case.....

It is not a great idea but it can work till you shear off the ring gear bolts under load..... Some of the aftermarket gear manufactures also made gears especially for putting low gear in a high case as well... . They were mostly for drag racing cars..... Not worth a dam for street use ..... They will ring like a bell during coast or deceleration... .



If you are still using the 727 3spd trans your top speed is going to be low ... .

One thing you can do is to use a 9. 00x 16 lt tires... . But the front fenders would have to have the corners clipped to clear them.....



If it were me I would just put a Getrag 5spd in it and call it done... Then when the rear blows get a 3. 55 and replace the axle. .



I have been considering having some 3. 07 made ... . but I am figuring that most of the housing's are junk now and that there will not be enough demand for them... . I also have been considering making some 3. 07 that will fit the 3. 55 housings ... . But I am not convinced there would be enough demand for them either... ...

 

[1stgen4evr]

From and to Mysteryman

"not convinced there would be enough demand for them either... ... "



I expect you are dead right on that. When you do the numbers, you get to your other recomendation. Just put a Getrag and be done with it. However, I am sure the Cummins will pull a 3. 07 AND OD. And with the right driving technique, would serve well. I think I recall that Phillip has that combo. I have been doing some swaping and have a 3. 07 that I plan to put in the 93 work truck (with Getrag). I figure to stay out of OD loaded and use the OD comming home empty. My total loaded weight is less that 19k.



Do you have any knowledge as to why there seems to be a high failure rate with the 3. 07? Or would you say that the failure rate isn't really higher, just more serious when it happens.



Wouldn't you think that the driver side carrier bearing would really suffer under the offset load of installing a 3. 07 in a 3. 54 housing? Would the Dana 80 be a better candidate for a 3. 07 retro fit?

James



Edit: Phillip, why don't you post to that thread and bring it to the top. There are quite a few members (myself included) that were not with us when that post was started. I think it would enlighten considerably on the configuration of the 3. 07 housing/gear set. Reference it to this one and tie it all together.

 

[Philip]

I brought that thread I linked to back to the top.

 

[MMiller]

However, I am sure the Cummins will pull a 3. 07 AND OD. And with the right driving technique, would serve well. I have been doing some swaping and have a 3. 07 that I plan to put in the 93 work truck (with Getrag). I figure to stay out of OD loaded and use the OD comming home empty. My total loaded weight is less that 19k.

*I* believe that unless conditions are extremely hilly that a mildly bombed cummins could pull good sized loads in OD with 307s, with stock size tires. The only drawback I see is getting the loads started. If you have a pavement only truck, then this is much less of a problem.



*I* also agree with pulling direct loaded, and OD empty, thats what everybody says to do anyway, so why not gear the truck so it runs down the road without excessive rpms.



With my 355's, and 33" tall tires I still use OD towing very heavy, and I find that at 60 mph, it could use a little more gear in 4th. I however run enough soft areas, gravel roads, fields, that 307's are too tall for my 4X4, 355s are a good all around gear for me.



Michael

 

[BushWakr - RIP]

Ummmm... ok, I just kinda 'scooted' to the bottom here ... . I notice the truck is a 4X4.

If the rear diff has been swapped out you might want to check the front ratio as well... . hopefully they are the same... .



pb. .

 

[Philip]

Guy's I have pulled a 12k load with my setup before. On flat ground it does all right. It does take some time to get to speed. I didn't use OD on those pulls. If I am hauling a car or truck on a trailer that doesn't go over 6k to 7k. I use OD all the time.

 

[MMiller]

Guy's I have pulled a 12k load with my setup before. On flat ground it does all right. It does take some time to get to speed.

I can believe that on a bone stock truck like yours. I was just saying with some bombs(more fuel+5spd or tight auto), those problems would not be as noticable. How much does your acceleration suffer from your convertor slipping(assuming its stock)?



Michael