I'm in the market for a new differential. I've found pumpkins from ecklers, corvettecentral and zip that seems alright for $800-920, zip being the cheapest with 800. Does anyone know of the quality of zips rebuilt differentials? Is there a reason like lower quality or no extras that make the $100 less?

 

Did you try Van Steel? They can rebuild your differential. Also Gary - GTR1999 - rebuilds diffs and has a great reputation on the forum, as does Van Steel.



Rick B.

 

gtr1999 will build up a better diff than anywhere....

 

try fastcorvette.com

 

try fastcorvette.com

 

try fastcorvette.com

 

Jontis,
The two best builders are right here on the forum. Gary (GTR1999) and myself. The difference is the quality of the bearings, posi set-up, and gear pattern. Not to mention deburring and polishing. Is yours not rebuildable?
Mike

 

yeah bearing quality...man the ecklers bearing kit sure leaves a lot to be desired, the stub bearings have half the rollers of the original ones..sure won't use those

 

I have been checking out the differential threads for a while and noticed the great rebuilders on the forum. My diff is partly rebuildable, except that the ring gear is damaged. The problem is that I am in Sweden, shipping here is 2 weeks and $300 one way and I need the pumpkin in working condition quickly. Also note that a shipping of $300 and core returns around 400 - damaged ring gear, it seems almost like a loss to return the core. That's why I'm looking at buying a new / rebuilt from the vendors.

So, anyone know where to order a full differential of reasonable quality for reasonable price?

 

What year vette and what gear ratio do you want? Auto or 4spd?
Mike

 

Been there and done that. I won't make that mistake again.

BTW, if you go this route add the core charge to your final cost. I wouldn't say they won't pay you for the core but you probably will spend more $$$ on phone calls than the core is worth.

 

Without getting too involved in a discussion about FCorvette.com, their quality went to crap they day after I stopped building their rear ends/trailing arms/gearboxes. Nov. 1st 2004.
Mike

 

The car is a 72 with manual 4. It had a 3.08 that I was happy with. I'm thinking of going with another 3.08 or a 3.36

 

Hi guys,
Just a note here, 308 & 336 were out of stock for a while so you might end up with Richmond or Yukons. I still use Tom's gears. I had one set of 336 and 373 left. When Tom back orders they take a while.

Mike is certainly capable of building an exceptional differential, like myself he puts a lot of time into them.

Regardless of who you decide on using ask what parts are used, which gears, kits, bearings, procedures, clutch type. All jobs are not alike.

I'm doing a differential now that I've spend 5 hours on just cleaning and deburring it. I now have a clean housing with a drain plug hole I tapped. Some places will pop out a rebuild in the time I spent cleaning them.

Good luck. I just shipped a lot of parts to Sweden and the shipping cost was indeed high, add to that you have what, a 24% tax?You're better off paying the $500 core charge then trying to ship it back to the states.

Do you think there is enough business there for me to open a vette shop? LOL!!

There is no way I could build a differential for some of the prices I see advertised,unless I just installed a master kit and clutches without any custom work. I pass on these jobs as there are plenty of places selling them.

Can you build one yourself? I have a "student" here - Gyopp did an excellant job as did a few others I walked through.

 

I might be persuaded into trying a rebuild of the differential myself. Just fearing that the carrier might be cracked too, in which case I'm surely better off buying an full assembly.

The tax here is 25% + a few % customs for importing stuff from backwards civilizations (that is on sale price + freight also).

If you are happy rebuilding differntials for other old american cars also, there is plenty of business here for you. If you only work on corvettes, it can be more difficult.

Where do you buy the parts you consider good? What should I ask for to know that good parts are used?

I'm not intending to race the car. Stock quality is enough for me.

 

The parts I use are from several places as well as kits I make up myself.
If you are interested in them just PM me.

Yeah I only work on corvettes, well another opportunity lost!!!LOL

I have seen some pretty cheap kits on the market and e**y. I use Timken bearings and CR seals, National pinion seals are ok too but I don't like their yoke seals.

If you remove the rear cover and rotate the case spray some brake cleaner on the pin hole in the case. If there are cracks you'll see them show up with the cleaner.

 

I've noticed there are modernized clutch packs available. What's your opinion on carbon clutches?

 

My opinion on those is to store them in the trash can. I had one set start to come apart in my hands and I refused to use them. Buyer beware. I only use the solid steel clutches set up without the springs. They last and I have no hammering from them.

 

I was just reading one of your (Gary) posts from early 2006 where you totally cut down carbon clutches. However, the general things I read on carbon clutches, not related to antique corvettes, is that they provide a smoother ride and last longer, thus being an upgrade. Could it be that the ones you saw was made on a monday? Just my humble thoughts, having no first hand experience at all and just quoting what other people have written.

Also, if you set up a diff without springs, only shimming, will you need to reshim it regularly to keep the pressure on the clutch pack when it wears?

 

The carbon fiber clutches I had were brand new and I have heard of trouble others have had as well. They come in the new Eaton units as well and I usually remove them for the steels. I won't use them in my cars or the jobs I do, maybe someday they'll convince me but as long as the solids are avail that's what I'll use. Hot Rod had a story on Tom's 2 years ago and they covered these then as well.
I have not had to reshim the posi's.

True there will be some wear but much less once those springs are removed from them. They are setup to tigher backlash spec's. One of our vettes has some HD use on it and the posi works fine. About 10k miles and the clutch is worn but the posi clutches are not!
As I have said many times, this is the way I build them, it is not the stock procedure and I'm not the originator of it either, that I believe was Pepe Estranda out of CA back in the 60's.