rear end ideas
 

This rear end came out of 83 300sd, there are part numbers on it. I'm trying to find the ratio? My current 240d 4spd has stock rear end, which I would also be wondering is 3:69?...Here is the numbers if anyone can help...thnx (1153513208)-and-(1233510101)

think its 3.08 in the sd.. def 3.69 in the 4spd.. man, rear ends are great.:D

Wouldn't that be so much better? Oh I hope because then I'm doin good right?

was exploring this avenue before..
but have been convinced that the 3.08 is too big for the 4spd n/a 616.

it is the 3.46 rear from the automatic n/a 123chassis that are the easter egg.
the 2.47 most definitely is the desirable turbo route.:D

Whoa, I have 617.952 4spd, so this rear end would be awesome correct, at least better on the interstate. If so I'm on my way to swap like 2sec from the garage and its on...Thnx for the replys I hoping this will calm rpm's at cruise...

The 3.69 is fine for me.

Well the low end is awesome, but high end blows. This rearend is just laying here in my shop and hell if I can gain something why not?...I read 60mph at 2000rpm and she sounds like its screamin lol....Hey thanks guys, for this. We are waiting to blow this out real quick...

rear end ideas
 

I'm not allowed to have any rear end ideas in this house.
Wait, was that out loud...........:silly:











:D

Either you ment 3000rpm or you already have a 2.47 installed....

Hmmmm, then maybe the tach is off...Anyway to read its signal with a meter?...So what about the diff swap here, will the 3:08 yeild something?

this.. :thinking2 ..would be the voice of reason 617.952+4spd combination..

are we talking about changing the differential in your 240?
feel like there's apples and oranges flying about..

I think a 3.08 would be too high a gearing for a stock 240D. It *will* make it slower around town and during acceleration.

Ok here...I have 617.952 4spd 240d same car as forced...I have triple k turbo 3" exhaust straight ...with 3:69 rearend...I have spare 3:08? laying in the floor...I asking about the gains or losses of this swap...my interstate cruising seems harsh with 3:69 in 4th gear...better?

Much better, I thought it was a stock 240. :D In that case, a 3.08 should be a good match. I just like the extra acceleration/torque the 3.69 puts to the ground.

Also, the SD and D will need different axle shims. You should be able to swap them across.

sorry:D.. that changes a whole heck of a lot..
yeah.. bet THAT swap would give some sweet hwy cruise..

Ok cool...So the swap will work with lower rpms in 4th at 60mph correct?

Ok lets make real sure...
CURRENT CAR
81 240D 617.952 4SPD 3:69 CONVERSION
DONOR REAR END
83 300SD 617.952 AUTO 3:08 STOCK
I will be placing the 3:08 into the 240D 3.0<-correct?

positively.. that would be outstanding on the open road.
forced is the sage though.. calling shims out of the air. :book:

Well cool to work I go....I wil post results shortly...Has anyone tried this combo before? Like you forced?

When I still had mt TD, I swapped the 3.08 for a 3.46 from a non-turbo 300D. It can be done with normal tools. It just takes time and alot of strength.

Be sure to have a long breaker bar available, get the car as high in the air as you can get it, take the axles completely out, swap the shims, and you might have to use the 240D's rear case/mount.

Well I'm hoping the rearend will make my car more interstate friendly...any ideas on the loss of lowend? The 3:69 is fun but man on the cruise it hurts..engine seems to be screaming..will see shortly though....any suggestions will be thankful....

Seems lining up the rearend is becoming a pain, round 2...

Ok now thats much better...The 3:07 feels nice and the engine dosen't sound like it's screaming...Oh and there is still plenty of low end power...Thanks for the advice

great to hear it.. and might add timely. nice work.:thumbsup:

I bet it's faster to 60 now too. The 3.69 does not allow boost to build in 1st and requires too much shifting. How is it off the line? Do you have your ALDA adjusted? I plan to do the same swap eventually.

the word?
 

A few months ago, I bought a bunch of parts from some dude, and included was the rear diff and (2) good-seeming shafts off an unknown doner.
The donor diff has "R 1153513208" stamped on it (the same as the OP of this thread)...but I've looked everywhere and don't see a ratio.

I've got an '85 300TD wagon with what I imagine to be both a worn differential and a bad axle shaft on one side.

(The whine sounds like a ghost creeping up on me when the drive shaft is loaded...typically around 20-35 mph. Changing the oil didn't help. When you put her in Park, she'll "rock back" quite a good bit.)

Anywho, I figured I'd replace both the differential and the axle shaft(s) at the same time.

Anybody know the ratio of the donor rear end and that of my wagon? Any way to test a rear diff for wear/noise when it's not in a vehicle? Thoughts about whether I can/should do the swap?

FORCED, you say the axle shims are different from the "D" and "SD" Differential, and to swap them.

I think from what I have read from other axle threads etc, the shims are specifically for each Differential, and not to swap sides. Let alone to swap them from diff. to diff.

Or am I not filtering the input through the bone structure and something is lost in the translation?:o

Charlie

Check here the lower left corner.
http://www.peachparts.com/shopforum/...1&d=1233343037


But to be certain of the gear ratio, remove the cover and count the teeth on the ring gear, and divide by the teeth on the pinion gear to get the ratio.


On your Euro, if you have a non-turbo motor. Then most likely you have a 3.46 ratio diff.


The only thing I can think of is to open it up and look at the ring gear wear and check the backlash.

Sorry Charlie,

I am thinking Lance will not be answering your question anytime soon here.:eek:

http://www.peachparts.com/shopforum/...1&d=1233343329







.

Not again? :confused: :eek:. :( he is a good conributor here on the forum, has a lot of knowledge.
Sometimes not a lot of tact or people skills which rub some people the wrong way. Just thined skined:P.

Oh well. Richard maybe I just misread what he was saying. I know to use the same shims on their proper side of the Diff.

I was reading that what he was saying is to swap them between Differentials.

I think they are sized to take up the space between the axle end, and where they butt up against the inside of the Diff. depending how the Diff is set up inside with shims and preload.

Charlie

shims should go with the differential. on mine they were the same from left to right but completely different for each diff, but I would check them side to side to make sure they are the same.

aha!
 

found it.
so, the 'donor' diff says 3.46 and the 'current' diff that's on my '85 wagon says 3.07.
i don't believe i have the shims for the donor...as he just gave the the differential itself, nothing mounted to the car.
does it sound like a bad idea swap anyway, for a 70% highway driver?

also, how do you know when an axle shaft's bad?

I wonder if its any different than when a CV joint starts to click on FRNT wheel drive cars?

any noises besides the Diff. Humm?

That isn't the swap you want to do for better highway RPMs and mpg.

If you HAD the 3.46 installed and were talking about swapping IN the 3.07 then you'd be going in the right direction...

With a 3.07 in there if you want to get even lower highway RPMs and mileage, you have to go to the 2.88 ratio - from the 85 300 series IIRC, or one of the 2.47 ratio rear ends from a gasser.

You can get the same effect as the 2.88 ratio by increasing your tire size by about 6%-7%. For example going from 195/70/14 tires to 225/75/14 tires is about a 6.5% increase in diameter.

You can't get the same effect as going from 3.07 to 2.47 with bigger tires though. That is a nearly 25% increase and you can't go to tires THAT much bigger - that would take a 315/80/14 - basically a truck tire that wouldn't even come close to fitting.

Now, if you want to make it a smokin' 0-60 machine, go ahead and swap in that 3.46 diff...