3.27 rear end

[DavidBrough]

I’m one of those who had problems with plugging the cooling tube holes and they were pretty dramatic. When I first fitted my 3.46 axle I plugged the holes and oil leaked from the breather very badly neatly rust proofing the entire rear end and fuel tank in the first couple of miles. I tried many different types of flexible hose but, for me, there just wasn’t enough room to give satisfactory clearance between the body and prop shaft during long suspension travel over rough surfaces. As a result I had the chassis altered to make room for the standard tube and all leaks were immediately cured and there’s sufficient clearance even on maximum suspension load.

[Garry]

I take back not knowing anyone who had problems with plugs.

I would suggest try the cheapest solution first then work your way up.

[GGR]

Cheapest is to use a BFH to make room for the original tube. By carefuly hitting the hedge of the chassis rail there is a way to shape it nicely,  threat it against rust and recoat the area with blackson.

Most elegant is to shape a pipe that clears the chasssis rail.

[Benz Dr.]

I'm not going to cut up a car to satisfy a problem with a simple solution. I've provided that answer and no one seems to be listening.  Move the vent tube to the original position when you have the axle out of the car. We used the smaller sized vent from a 280SL axle. After looking at the size of the one on ther 4.5 it's little wonder why oil spews out when it gets hot.
Placing the vent on the side of the diff housing reduces the chance for oil to come out. The 6.3 should run hotter than a 4.5 yet nothing comes out of the vent that's placed right on the axle tube.

[hank sound]

    Hey folks,  

The 3.27 is in - along with new B. shocks (all around), bushings, pucks, seals, wheel bearings, etc, etc.   Pics also of the new cooling tube with custom fittings.   The next few that we make will be even lighter and with "cooler" fittings - AND NO MODIFICATIONS AT ALL.    

Ingrid is now truly a joy to drive.    Yes, if starting off in the normal second gear of Auto, she's a bit of a slug in town.   Well, we just hand select 1st, and all is OK.     On the freeway, the difference is absolutely amazing.    As I was blending in with FW traffic, I wanted to see how the kick down worked while changing lanes and getting past an 18 wheeler - - Woo-Hoo !!!   Now the kick down is there, when and where you would probably most need it!      IMHO, this is the way MB should have done it all along.    

A huge thanks to Dominic & Vicente @ EUROSPORT in Burbank, CA.     Their attention to detail is beyond description !!!

Will keep you all posted on cooling tube progress, in a new thread called (drum roll) "3.27 Cooling Tube" - soon..........

Cheers, Hank

BTW, the post below, posted by me, is a mistake.    I couldn't find a "delete function.

H

[Garry]

Hank,
is there a fitting behind the universal holding the hose?

Garry

PS Deleted your double post.

[hank sound]

   Thanks for taking care of that little "delete" issue.   Yes, there is a fitting - and it's just for insurance.  

Cheers, Hank

[glenn]

GCR, What is 'blackson'?

[GGR]

GCR, What is 'blackson'?

It is undercoating :

[hank sound]

Hi .................. Ingrid's first 100 miles on freeways around Los Angeles with our new 3.27 rear end, were absolutely spectacular !!   Sure, with an auto tranny that starts in second, she's a bit slow off the line.    But if I need to leave the line more rapidly, I just put it in first and then do the manual shifts.  

Key here (for me), is that at freeway speed, I'm 800+ RPMs lower than with the original 3.92 ratio.        

Cheers, Hank  

[hank sound]

Giggle - giggle    OMG!!   This new rear end ratio is blowing me away.   In town, I now start out with my auto selector in first.   It puts me more in touch with the performance capabilities of the engine.   So, I can start out rapidly if I choose - - but once on the freeway, it's truly a cruise !!

Cheers, Hank

[Michael C]

Just put a new vent on my 3.27 rear end and it is dripping oil.  (Not overfilled) Today I ordered all of the fitting (As pictured in an earlier post) to make up a new bypass tube.  I had the tube removed and holes all blocked off for years.  Never really paid attention to it until this post.  My old vent was all clogged up so it never leaked.

[jeblack123]

I am about to have my rear end changes to to the 3.27 from the 3.92. I know that Hank Sound's mechanic is still perfecting his flexible replacement tube, but until it becomes available, I am thinking about plugging the holes as others have suggested. my question is what are people using to plug the holes left after removal of the rigid cooling tube on the 3.27? After installation on the car will the plugged holes be accessible to have a flexible tube added in the future if it is necessary? Without the tube, will my car be less capable of longer drives because of a heating issue in the rear end? Thanks for all of the help.

James

[pagoden]

James -
The holes plug neatly and simply with drain plugs.  I blush to admit I'm not sure of which ones, but it may even be all three: engine, transmission  and differential; the ones that work take a 14mm Allen/hex wrench screw quite nicely into the holes left by removal of the cursed tube.  [I'm just now realizing I've never actually verified the donor locations for the plugs, but our veteran members will know without having to give it a thought.]  But it is simple and tidy and accessible for later changes with axle assembly installed.
The consensus amongst our wise heads is that overheating, with our cars having significantly less horsepower and weight battling it out, is not going to be a problem.
My experiences with oil blowing out the vent and the good Benz Dr's recent calling to our attention an improved location for the offending vent leaves me wishing I'd had your opportunity to try installing that modification prior to putting in my 3.46 axle.  Even better, before re-assembly during your inspection and refreshing of whatever's necessary in the donor axle.  Drilling and tapping in that location on the assembled axle is only practical with it out of the car, and then best done by someone with considerable practical experience due to the potential for sprinkling nasty chips of iron inside the works.
Tube removal and plugging is simple.  In fact, it begins to look like all you might have do to avoid the distressing barfing of the 90wt. is to refrain from cleaning (clearing) the vent assembly.
[No, I don't seriously suggest anyone employ that as a permanent solution, but it does begin to look like it may be the explanation for the otherwise apparent randomness of these occurrences.]
I think the Dr's onto something good here.  Well, it is a bit of early days but through my dim and distant glass it appears an elegant diagnosis and remedy, so I am in hopes the bugger's vanquished.


 

[GGR]

I just did what Dan suggested regarding the vent. I did it on a disassembled wheel tube and I got metal chips inside it. I don't know how one can avoid it. I wouldn't take any risk as these metal chips fall right next to the diff bearing with potentially heavy consequences once they get inside the bearing. It's a good occasion to disassemble the wheel tube and check all bearings anyway. It's not complicated and it's just a matter of bolting it back with new sealant if everything checks in good shape.

[philmas]

Did you see this item on the SLS catalogue?
As far as I understand German, it looks like a 3.25 replacement gear , requiring  "modification" of the diff case (?)
Any thoughts?[http://www.sls-hh-shop.de/index.php/cat/c3_Mercedes-Benz-230SL-250SL-280SL-Pagoda--R113-W113-.html#cat_120

[jeblack123]

Does anyone have the P/N for the drain plugs to coved the holes left after removal of the tube?

[Benz Dr.]

I had it apart when it was drilled but you could use some grease which will hold the chips from falling into the axle. Use the smaller vent found on a typical 113 axle and not the larger one found on a 4.5

[naniroma0]

Did you see this item on the SLS catalogue?
As far as I understand German, it looks like a 3.25 replacement gear , requiring  "modification" of the diff case (?)
Any thoughts?[http://www.sls-hh-shop.de/index.php/cat/c3_Mercedes-Benz-230SL-250SL-280SL-Pagoda--R113-W113-.html#cat_120

hello,
information you found?

[ja17]

I've been told that these gear sets from SLS, are actually, physically smaller in size than the V-8 gears, but they are the same ratio. They will fit in your original differential housing, after a machining operation, so you change out the gears only and keep your original rear axle assembly.

The downside is the expense of the gears, the cost of the machining and the very complex procedure to set-up the gears.

Joe Alexander (ja17)
Blacklick, Ohio

[Benz Dr.]

I've been told that these gear sets from SLS, are actually, physically smaller in size than the V-8 gears, but they are the same ratio. They will fit in your original differential housing, after a machining operation, so you change out the gears only and keep your original rear axle assembly.

The downside is the expense of the gears, the cost of the machining and the very complex procedure to set-up the gears.

Joe Alexander (ja17)
Blacklick, Ohio

Joe,
you're getting soft in your old age.
 Imagine; you giving advice that's more work and complication than it's worth...........

[ja17]

Hello Dan,

Actually, one learns to work "smart" as time passes. It minimizes the hard work!