Am I getting scammed?

[Finn]

Ive got my 8 3/4 back in the differential shop because during some test rides around my block I noticed a howling noise while coasting. It started faint and got worse so I took it straight over to the shop that put the sure grip unit in. Now, they tell me there's no fluid in it and because of that my gears and bearings are shot. Ive gotten past the fact that my dad and I both remember them telling us they put fluid in it because I should have checked it first either way.

Now I figured I might as well go to 3.55s from 3.23s since I need new gears anyway. His quote comes back at 630 bucks and he says they would have to be 3.91s because my pumpkin is a 42 (not the 89) and wouldn't work with 3.55s. Ive never heard of 3.55s not fitting with 42 case and 630 seems way high.

What do you guys think?

[tan top]

the guy who done your centre section could be getting mixed up with the 741 
check out this link ,  mancini do then 742 center section with 3.55 gears     

http://chucker54.stores.yahoo.net/comcen.html

[Troy]

Uh, are these guys professionals? Sounds like they don't have all the facts.

From Dr Diff:

New ring and pinions for 742 casting (10 spline):
3.55, 3.73, 3.91, 4.10 $185

Does the $630 include filling it up with gear oil this time? Did they install the entire pumpkin and let you drive it home from the shop the first time or did they just add a Sure-Grip and hand it back to you? If they did the complete install then they're responsible for putting fluid in it. If you purchased installed it then I'd say it's you're at fault.

For comparison, Dr Diff sells complete 742 pumpkins with brand new bearings and gears and a new Sure Grip unit ($350) for $950. Yes, his prices are generally better than others and you'd have to install it yourself. Sounds like their prices are comparable - but not if they screw up another one and you have to pay for it.

Troy

[1BAD68]

I wouldn't let that place do any more work, it seems they dont know what they're talking about.
I run 3:55's in my 742 case, I bought the gears new and a clutch kit from DrDiff and did it myself, not that hard.

[Finn]

The entire diff and housing was out of the car because I was still working on the 4 link at the time. They put the sure grip in that I got from Randy's R&P along with the axles and backing plates then I took it home in the back of my truck and put it in the car. The receipt I have doesnt say anything about fluids but I remember different...Either way, there's no proof of anything and I should have checked.

The 630 does include the fluids and after some more searching does seem within the ballpark but when he told me I would have to go to an 89 case I got suspicious. 3.55s ARE available for the 742 as tan top pointed out, and they're right there on randy's R&P too.
I dont know if I should tell him they are available, order them myself, and have him put them in or not. He also said he couldn't be sure whether the sure grip was affected or not without taking it apart.

I probably only drove 2 miles so far and never got on it, but I also don't want to have to do this again down the road.

[Finn]

I wouldn't let that place do any more work, it seems they dont know what they're talking about.
I run 3:55's in my 742 case, I bought the gears new and a clutch kit from DrDiff and did it myself, not that hard.

Would I need any special tools to do it myself? I'm strongly considering it right now.

[mikepmcs]

yeah, like has been said.  i wouldn't go back to them for anything at all cause it appears they aren't that knowledgeable, which is enough for me.  then i would get the word out that they are not a reputable shop and hit em where it hurts.

you can do this yourself IMO. as far as tools go, here's some(besides basic stuff)
Dial indicator
Ft.Lb. torque wrench
Dial In.Lb. torque wrench (0-50 In.Lb. or so)
Pullers and/or Press for removing and installing pinion and differential bearings
Spanner wrench (for many drop-out carriers)
Compressed air, and 1/2" impact wrench is helpful


Read this article
http://www.mopar1.us/setuprear.html

Don't be scared, just be diligent, focused and have attention to detail, like in your photography!
Have plenty of patience as well.

[Troy]

Ah, if you just picked up the entire rear end I wouldn't have expected them to fill it (accidentally roll it over and all the fluid would drain out of the vent wouldn't it?). Yes, you should have checked. So really, you have no idea if it was built right or if the lack of fluid killed it. They may very well be a top-notch shop and just had a brain fart and didn't know what gears fit in what OR someone spouted off without actually looking it up first OR their particular supplier doesn't happen to have that ratio for the 742.

Call me a wimp but I'd rather trust someone with more knowledge/experience than myself to set up the gears properly. The cost is worth it in my opinion because bad things can happen (I think you're lucky that nothing locked up on you and caused an accident).

If you'd rather have 3.91s them send me a note since I have a spare.

Troy

[Finn]

Thanks for the replies guys. I talked to him again and he explained his statement on the 3.55s in the 742. According to the guy company he orders his ring and pinions from, the Randy R&P 3.55 for the 742 isn't the best quality and customers frequently report a whine after install. They don't get any complaints on the 3.55 when its for a 489 however. He called them and let me talk to them about it so I don't doubt it but at the same time Ive never heard about anyone having that issue on here. Still haven't decided what to do yet.  My savings would take a big hit but I'm also running out of time before school starts back up and Id rather have the car back to driving condition before that happens.

[TylerCharger69]

I havent heard of anybody putting fluid in a rear assembly if it was not in the car.   Now if they assembled and installed the unit...i would expect them to.   Im willing to wager it was empty when you picked it up.  A lesson well learned.   The price seems a bit steep though.

[Belgium R/T -68]

I wouldn't consider doing it myself, heard a lot from friends who tried that problems occured afterwards.

Per

[bricklayer]

I just read the 1st thread and that would have been enough for me get your parts and pay them what you think you owe or not and find another shop or if possible get an entire 3rd member complete from mister gearhead good luck  tom