Traumamatic

So, I picked up a QDF7V in hopes of installing it in my car. Although it was stated by many retailers to fit these cars, there is no way to reinstall the circlips onto the axle input shafts if it were to be installed. There is clearance through the OEM open carrier to reinstall the clips, but not through the quaife.

In digging through this and other forums, I saw that some users attempted to run the differential anyway. Some reported no issues (they must put around turns), but others reported axles slipping out (which is what I would expect following severe fluid loss).

After reaching out to Quaife, if appears that there is only one official\proper solution. Regretably, it is so expensive that I'm having a hard time justifying it on one of these cars at this point. Quaife support directed m to Byrd's Automotive in the UK. Byrd's commissioned a special version of this differential (part# QDF28B) that is designed to accept snap rings instead of circlips. They machine a pair of SL55 output flanges to work on the W210 that are required for proper utilization of snap rings. The differential is $1350 shipped + VAT. The modified output planges are another $950. Bird's Automotive was extremely helpful and knowledgeable.

I put the upgrade on hold when I realized that it was going to run me ~$3000 in parts to properly complete.

I've heard about people putting tube around the flanges and hammering them into place for retention, but I'm not willing to take such a risky approach on such a critical mechanical part. Has anyone found any alternative solutions? How are the axle flanges retained on OSgilken carrier installs?

The lack of a mechanical LSD in these cars (or any remotely performance-oriented vehicle) is an absolute disgrace to the platform!

Quant

iTrader: (1)

i'm one of those that had issues, but the fix that i put in seems to be working (bolt with bearing to keep axles in place). with that said, i might consider this new 950 option as this is always something thats on the back of my mind. my recommendation for anyone going through this is to go the BlackBenz route using w209 amg housing with wavetrac and custom beefed up axles.

Traumamatic

Thanks! I'm still reading through BlackBenzz's build thread. It looks like he welded a mount onto the subframe and spent a pile of money on custom axles that he waited an exhorbitant amount of time for to get that differential to work. That's probably going to end up being far more difficult and expensive to pull off than just buying the parts for the Quaife solution from Byrd's.

Did you happen to take a picture where you installed those bolts?

turbo1k

I installed a phantom grip in my car and used clips from a FWD style axle. They just popped right in. Been 5 plus years and 50k miles without any issues.

Steve

Quant

iTrader: (1)

see attached files. in addition to this i also installed bearing at the end of bolt so that it spins with axle - without it the bolt was breaking!

Tall Giraffe

On thier site they have a single product for the W202. Is that what you used? and the clips comes from where a 4Matic W210?

turbo1k

Honestly not sure. I called and spoke with a tech guy and he decided what i should use. Im sure they still have a record of my sale.
I want to say it was $459 5 years ago. He are the mods i had to do for it to work. I beveled the gear so the clip would slide it and not push off.
I used clips from a few used mitsu axles i had hanging around. I had to grind the PG end blocks for the correct spacing that they told me i needed.
I included pics of each.

Traumamatic

Thanks Quant.

Unless I can find a shop with specific experience performing this axle flange modification near the Atlanta area, I'm giving up on pulling this upgrade off. The engineers and\or beancounters at Mercedes who decide to sell AMG model cars without LSDs should be ashamed of themselves.

ccrelan

I would reach out to Jonathan at Blue Ridge Mercedes just outside of Atlanta if you live down that way.

Quant

iTrader: (1)

i agree, how the car didn't come with Lsd is beyond me. my 1986 190e 16v had one from factory, so surely they knew it was good for perfomance driving!! if you want to send me your diff i'm happy to give to my shop to do the required modifications. my recommendation is to honestly just pass on this, will cost a lot of $$ and create more headaches than its worth.