So i had the swap done at RAI motorsports. I provided them with the trans the axels and driveshaft and rear diff the rest they sourced for me. It was great for about 28 miles and then the rear diffirential exploded. Im guessing that no one checked to see if the rear diff had fluid in it. So i guess im buying a new rear diff and paying to have another one installed. tell me what you think.

 

Dear Audi gods... I'm praying to you today asking that you pleeeeeease never let this happen to my car!

Sorry about your hassles bro! You sure you weren't driving down a street in Iraq and get hit with an IED or something? That looks horrible! Just out of curiosity, is there an upgrade? That's how I get to justify upgrades to my wife... "since it needs to be replaced, I might as well spend the extra xxx bucks anyway, honey..."

 

I'm curious - what RPM were you turning in 6th gear at highway speeds? I don't drive my 2.8 hard (what's the point after all) but if the overall gearvratio in 6th is tall enough to drop the revs and improve gas mileage, I'd consider this. I could justify the cost based on an improvement in mpg and the relative uniqueness of the setup.

What else had to be swapped? Mounts? Driveshaft?

 

it wouldnt improve gas milage really, the gear ratio in 6th is similar to 5th on your trans, the 6 speed just has 6 shorter gears that cover almost the same range as the 5 gears on our trans'. its reallllllly not worth it imo.

 

Seeing the carnage makes my head hurt lol. I contemplated a swap, but I think I'd rather just get an S4 with 6 gears already in it

Good luck man! Any idea if the shop is willing to cover that, since you only made it 28 miles?

 

Ghost, that's the info I was looking for. I knew it wouldn't be basically the same 5-speed with an extra tall sixth gear but I was hoping maybe that rather than give the same overall range with shorter gears all the way through, that maybe they'd split the difference by shortening 1-5 somewhat, with a top gear that was taller than top gear in the 5-speed. That way there'd be the benefit of better in-gear acceleration and a bit more of a relaxed cruise RPM in 6th. Oh well.

 

i have a ton of spare parts now. a4 carriers, a4 axels, s4 front axels, 5 speed a4 trans with 2nd gear issues, a4 rear diff, a4 driveshaft, let me know what you need and i will take some pics

 

Here is links to rpm/mph for the B5 A4 2.8, 1.8t and B5 S4 01E transmissions. Also the rpm for 75 mph in top gear.


2.8
75 mph at 3210
80 mph at 3425


1.8t
75 mph at 3410
80 mph at 3635


S4 6 speed
75 mph at 2940
80 mph just under 3140


BTW really low rpms at fwy speeds does not aways mean better MPH, if the rpms are too low it takes more throttle to keep the car at that set speed. Also remember that the S4 makes makes more power off boost at low rpms then a 1.8t.

 

ouch, thats crazy! keep us updated when u get the new one on, hopefully it wont blow next time!

 

I myself am contemplating a swap. I have a 2.8 now but I was considering a 6 spd ( I bent 2nd gear synchro in my stock 5 spd) trans this summer and next summer the 2.7tt swap + some extras. I want to make it around 425 awhp. Any suggestions on the diff, clutch or the idea as a whole?