Gear Change

[ramrod]

I have a 93 Convertible - Automatic ( 33K miles ) ...I have a K&N filter but otherwise stock. I am about to take the plunge and change out the rear end for a 3.54 gear set.

I'm contemplating ordering the Ecklers complete rebuilt differential
( part # 43835 ) for about $995.

I'm open to comments, suggestions or alternative places to buy. I'd also be interested in others experiences with Ecklers rebuilt differentials.

I thought about just rebuilding my existing diff, however, I have heard that this can be tricky inserting and aligning the gears ...seems to me that the simplest and safest for me is just replace the diff. as a whole with the new gears installed.

Guess I will also have to look into how to fix the speedometer ...perhaps the Ecklers package comes with a fix for this.

Thanks.

 

[Redmanf1]

It depends on a few things. You need a torque wrench, preload and dial indicator set to do crush sleeve and gear shimming. You would need to order shims along with the other parts. The other thing is what series carrier do you have? You need some experience to do these correctly. I think if I was you and I was going to pay that much I would buy one without exchange so you could put it back to stock if you want to sell. Just my 02.

 

[Redmanf1]

I have seen some recondition on eBay.

 

[ramrod]

Gears

I presume that when you said "..You need a torque wrench, preload and dial indicator set ..." you were referring to the option of my simply replacing the pinion / gears as opposed to my simply buying the entire differential.

Assuming I am correct, thats the very reason I am favoring buying the diff. with all the parts already professionally installed. I am reasonably handy and figure that I can install the new diff. myself.

I agree on keeping the original diff ...thats my plan.

Was hoping someone had experience with these Ecklers diff's or words of wisdom regarding alternate sources.

Thanks,

Rod.

 

[Corvette-Pilot]

I think if you go with Eklers AND keep your original they charge something like $400 core fee so your real cost is higher?

 

[ramrod]

Yes ...thas the way I read it. Assuming they are selling a quality diff with the gears all seated, etc., I'm willing to pay ...more expensive than just buying just the gears, etc. and installing in my existing case, however, I dont feel I'm sufficiently competent to handle that route ...I planning ( hoping ) that this will be a simple swap ...one diff for the other .

Rod

 

[Redmanf1]

Yes you are correct. Sorry I can not help your question on the quality of there rear, I always just bought the gears and changed them. I found one for $1100.00 no exchange. I guess just look at the warranty and shop price.

 

[oldace84]

3:54's, great choice.
Good Luck, and go for it.
tony

 

[-=Jeff=-]

Guess I will also have to look into how to fix the speedometer ...perhaps the Ecklers package comes with a fix for this.

Thanks.

Get the Speedo Parts from GM.. they used them in the ZF6 but should work in the Auto..

here is a linkf or GM Part #'s

http://www.corvetteforum.net/c4/vettenuts//SpeedometerGearshtm.shtml

 

[vms4evr]

I have a 93 Convertible - Automatic ( 33K miles ) ...I have a K&N filter but otherwise stock. I am about to take the plunge and change out the rear end for a 3.54 gear set.

I'm contemplating ordering the Ecklers complete rebuilt differential
( part # 43835 ) for about $995.

I'm open to comments, suggestions or alternative places to buy. I'd also be interested in others experiences with Ecklers rebuilt differentials.

I thought about just rebuilding my existing diff, however, I have heard that this can be tricky inserting and aligning the gears ...seems to me that the simplest and safest for me is just replace the diff. as a whole with the new gears installed.

Guess I will also have to look into how to fix the speedometer ...perhaps the Ecklers package comes with a fix for this.

Thanks.

Well here is my 5c worth. I did a swap from 2.59 to 3.54 about 18 months ago. The gears now whine quite a bit and I suspect they are on their way out. I had these setup by someone who has worked on C4s and built them for racing. He said they were a PITA to get in and setup. Now I see the outcome.

So I have to replace it. I still love the pull with the 3.54 gears. They're perfect for an LT1. I'm going to dump the whole diff and trade it in on a rebuilt. So...

The one you list from Ecklers is for an 84 only. For 85-96 they offer the 3.07 or 3.73. The 3.73 setup is pricey but it also comes with a new heavy duty bat wing. As I recall they get their diffs from Ikerds. And Ikerds is the only one I know of that sells a HD bat wing for the Dana 36. Take a look at Ikerds website. You could just cut out the middle man...

Also Zip sells rebuilt diffs with 3.54. I think someone posted on the other forum who rebuilds diffs for them. I didn't notice a warranty with theirs but the price is better.

MidAmerica also sells them and I'm not sure where they get them from. They do 12 mo / 12K mi or something like that.

As far as the speedo gears just search for 3.54 gears. I posted last year with all the gory details including the 2 gears and speed sensor GM part numbers. Along with the speed/rpm you will run with those gears in D and OD.

Graham

 

[lt1vert]

I swapped out my 2.59's with 3:73's from Ikerd's and have had no problems with the gears. No whine or noises. You might want to invest in a torque converter also if you're getting gears. Made all the difference in the world when I got mine.

The gears cost me 225 plus 100 for shim kit and gaskets, 600 for installation. Torque converter is best done at the same time since you'll only have to take the x-brace and tranny down once.

 

[vettn94]

I would buy one without exchange so you could put it back to stock if you want to sell. Just my 02.

Good advice, that's exactly why I bought mine (3.54 Dana 36)outright. I got it from:
http://www.partsforvettes.com/partsforvettes/index.html
ask for Ed, he's a great guy and stands behind his work 100%.
I ended up buying another batwing for around $100, saved time and mess while swapping. I used GM black silicone to seal the new cover, Ed recommended. The silicone needs to set-up overnight. Fellow fellow forum member Jeff helped with the swap, I think it took us the better part of an afternoon.
Good choice in gear, my ET & MPH went from 13.82@101 with the 2.59's down to consistent 13.30@105.5 MPH with a best of 13.23@105.91mph with the swap to the 3.54.

 

[-=Jeff=-]

Fellow fellow forum member Jeff helped with the swap, I think it took us the better part of an afternoon.

Would have taken less time if Nick was not complaining about taking the U-joint bolts out..

LOL j/k
:t :t

 

[vettn94]

LOL !!

 

[kingman]

????????????????

Hi

Why wouldn't you go to the 3.73 gears, instead of the 3.54.

Alan

 

[invinceablevett]

I put in 3.73 gears.My best time was 13.53 if my memory serves me right.I never timed the car before the gears.I had a little black box installed for the speedo(can't remember where in the US it came from.The new speedo is great but the gas guage seems to jump from 1/4 full to check guages(empty) really quick.It's a little annoying but worth the jump at the red lights.I like my 3.73's.

 

[Doutdoor]

Ok, I just had to post another message as I saw this topic which relates to a another mod I have just done as well. I did a lot of research about 5-6 months ago, asked a lot of questions & guys like Graham were a big help in my decision to go with the 3.54 gears in a Dana 36. I thought the 3.73's were a little too radical esp. in a Dana 36 and I like to cruise the highways. Anyway, I had a guy do the work who has done a lot of rear end work. My advice....find someone who knows their sh.. about doing this. My guy used Strange gears and I swear I have to listen real hard with the radio turned all the way down to hear the slightest gear whine at all, and mostly while decelerating. It's all in the setup. The mechanic even showed me on the box the new gears came in which says right on the outside "noisy". I'm very happy with the job he did. Another thing.....I was going to swap the pumpkin out myself with the help of my bro-in-law who's a mechanic and save some money. Went as far as dropping the exhaust system by myself. My bro-in-law took on look at it & said "whoa, bolt the exhaust back up & take it to someone who's done this before." Without the experience of having done a job like this, believe me it's worth the $400 extra bucks you'll spend to have a real professional do the job. Total cost for my gear change was about $1,500. And well worth it for the job he did. The car accelerates like a rocket and takes no prisoners.

Good Luck...:cool

 

[invinceablevett]

doutdoor......you're right about the car revving a little too high on the highway but I personally don't do much highway driving and highway suicide isn't my thing anymore.I do drive my vette some 350 miles down to R.I. every summer and it isn't so bad,for me.I regret not changing my torque converter as I am told it would have made a big difference on the launch.Did you change the torque converter?

 

[vettn94]

I had a 2800 stall Vigilante in my 94 for a short time. With the 3.54 gear my 60' times dropped into the low 1.8's with a best of 1.78 on drag radials w/ 18psi. That converter also knocked off a couple tenths from my ET.

 

[Doutdoor]

invinceable..... yes I changed out the torque converter to a 2500 stall. The trans shop I had the work done said they didn't recommend going to any higher than a 2500.

Dave