Thinking about going to 3.73's. What is the normal labor charge for the change. Thanks
Labor cost on Gear change
- Thread starter ditchsnake
- Start date
Going to a 3:73 is not worth paying someone to do it. I have 3:73's in my car I love them but I chewed teeth of my ring and pinion so I needed new ones. Its not that big of a difference to just randomly do it. Maybe 3:90's but the stock 3:55's are about perfect for the car.
I am going to guess 10 hours of shop time because when I called the service counter to ask about doing it on my old GT they said 8 hours and the IRS will probably take a bit longer.
I disagree with it not being worth it, small gearing changes can make a big difference. You will def notice the change from 3.55 to 3.73
Also, 3.90 is not available from Ford so I would not suggest that. Motive gears are harder to install so they will take more time and cost more labor hours.
I disagree with it not being worth it, small gearing changes can make a big difference. You will def notice the change from 3.55 to 3.73
Also, 3.90 is not available from Ford so I would not suggest that. Motive gears are harder to install so they will take more time and cost more labor hours.
i agree with kilgore that 3.73's do make a difference!! 10 hours seems like a long time to drop the differential only, set it on the table, and out with the old, and in with the new, and setting it correctly....:dw:
but then again, ive never done it an dwasnt there when i had it done, so maybe it does take that long..:shrug:
but then again, ive never done it an dwasnt there when i had it done, so maybe it does take that long..:shrug:
10 hours? way too much...the guy I bought my Cobra from, took the pumpkin out and took it to the best shop in town to change the gears to 4.10s for around $450...the previous owner of my car said the labor of taking it in and out+lift time is where they get you in the price...JMO
Do at least 3.90's. I run a3.90 gear with 2.2 KB and trap near 132 and I'm still not at redline when I cross in fourth. I pull 1.5x 60 footers easy on 17 inch ET Streets.
I've done several gear swaps on IRS CObras. Remember you have to pull the pumpkin. I can do a swap ususally in 3-5 hours. Make sure the shop can do it right by shimming to get the correct backlash and wear pattern. Put in some new IRS bushing when you do the swap.
I blew out the baffles in one of my Bassanis one winter. I called and they were on backorder. It rattled really bad. I took it to a muffler shop and had them make me a set of straight pipes to replace my mufflers. It was loud. I had recently had problems loosing boost because my dump valve was bad. I had discommected it. I took it out on a 30 degree day to see if the boost would hold. I got up to 80 in third. I slammed it to the floor, boost pegged at 21 psi and then the revs went redline. My first thought was my clutch was gone till I felt the car wiggling. I looked in the rear view and I was laying black stripes at over 100 mph. I laid down a set 100 yards long. I dynoed at 19 psi 611 rwhp SAE and 580 rwt. No telling what it was making that morning.
Believe it or not.
Good luck.
Labor should be around $400 + fluids/friction modifier.
X2, get the upgraded differential bushings, I got them on mine...
Great stuff
This is just what I was looking for. You guys agree the 390's are better? How do those gears run on the highway, RPM in 6th. I was worried I would run out of gear with them. Sounds like it's not a problem though. Don't care about the mileage. Bought my 04 new and only have 7000 on it. What kind of bushings should I use. Read the derlin are better. Is that correct. Thanks for all the great info.
This is just what I was looking for. You guys agree the 390's are better? How do those gears run on the highway, RPM in 6th. I was worried I would run out of gear with them. Sounds like it's not a problem though. Don't care about the mileage. Bought my 04 new and only have 7000 on it. What kind of bushings should I use. Read the derlin are better. Is that correct. Thanks for all the great info.
4.10s here at 70mph, I'm right a hair above 2250...the car pulls like a 600hp car in 2nd, lol
Do what I did with my 90 GT. Get a bidding war started with your local FORD dealers. I went to one and they gave me a price. I called the other in the next town and told them I was comparing prices for an install of rear gears and that I had already got the gears from Ford but needed installation only. They gave me a price. Called the first one back and asked if they could meet or beat the price. They beat it. I called the second one back again and told them what the first one said they could do it for. They beat it by $50.00. I went to them and they actually ended up only charging me $186.00 for everything. It started out at $500.00 so I ended up paying over $300.00 less. With the economy as bad as it is someone at one of your local dealers will NEED the work. Plus it does not hurt to ask.
What do you top out at in 4th with those 4.10s bro?
thank you!
I love saving money! means more mods. i'm going to call the ford dealers monday. any more thoughts on bushing types and gear ratio? 3.73 or 3.90?
I love saving money! means more mods. i'm going to call the ford dealers monday. any more thoughts on bushing types and gear ratio? 3.73 or 3.90?
Get the bushings a mod on here makes. I think they are down in the suspension thread. Im going to tell you first hand, you are going to be PISSED if you have to pay $400+ on 3:73's. You will notice a difference but its very little. If your going to do the gear then go to the 3:90's. If you research this topic more there are tons of threads out there giving you the same results.
If you want to send me the center carrier and new ring and pinion you want, I will install and setup your gears for $100. You pay shipping both ways. Just trying to help out. If you are interested just PM me. I'min central FL, so shipping should be like $50 bux.
The offer stands for anyone else that needs some help and wants to save some money. BTW the best gears you can get are the FRPP gears. Otherwise you need to make sure that the other brand (motive, richmond, etc...) have the pinion depth scribed in the top of the pinion, otherwise it make setting pinion depth a PITA!!!
Also, 4:10's will get you through the traps in the 1/4mile at just under 7000RPMs. And if you run a 28inch tall tire, like the M&H racemaster drag radials, it makes the car run closer to having 3:90's in it.
The offer stands for anyone else that needs some help and wants to save some money. BTW the best gears you can get are the FRPP gears. Otherwise you need to make sure that the other brand (motive, richmond, etc...) have the pinion depth scribed in the top of the pinion, otherwise it make setting pinion depth a PITA!!!
Also, 4:10's will get you through the traps in the 1/4mile at just under 7000RPMs. And if you run a 28inch tall tire, like the M&H racemaster drag radials, it makes the car run closer to having 3:90's in it.
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I know my 5.0 is a lot different than my terminator but WOW did the 3.73s I put in it awakened a beast especially since I put the supercharger on afterwards. Bad thing with 3.73s is with the BFG drag radials I had I had to let off at the 1,000 ft mark and coast to the finish line or shift into 5th/overdrive. With the McCreary street slicks whick are approx. 2 inches taller it was perfect. I know several fellows around here with the mod motors went to 4.10s. I guess it would be what a person wants.
OBTW, definitely get the FRPP gears. Mine bolted right in the 5.0 with no adjustments needed. Tech used the same amount of shims that came from the factory on the 3.08s and it was dead on the first go around testing the gap/clearance. Tech could not believe how easy the install was.
OBTW, definitely get the FRPP gears. Mine bolted right in the 5.0 with no adjustments needed. Tech used the same amount of shims that came from the factory on the 3.08s and it was dead on the first go around testing the gap/clearance. Tech could not believe how easy the install was.
Frpp
Those are the Ford Racing I think. I couldn't find them in 3.90's. Is that correct? If so I'll call Tousley ford again to make sure the pinion debth is scribed on the top of the pinion gear? Sent a PM to Florida. That's gotta be a great place to live. It's a great place to vacation at.
Those are the Ford Racing I think. I couldn't find them in 3.90's. Is that correct? If so I'll call Tousley ford again to make sure the pinion debth is scribed on the top of the pinion gear? Sent a PM to Florida. That's gotta be a great place to live. It's a great place to vacation at.
Also, one thing that no one mentioned is that the shop (or individual) performing the work, also needs a case spreader to properly set the pre-load on an aluminum pumpkin. If they try to use the same pre-load specs as an iron pumpkin the gears will not last because the aluminum has a much higher rate of expansion when it heats up. Doing an aluminum pumpkin is much more time consuming because it usually needs to be assembled, and broken down a few times to get everything in spec, and those specs are more critical than an iron unit because of the expansion. My minimum to do the setup would be $350-$400. As others have mentioned, go at least 3.90 or don't bother changing them. 3.55 to 3.73 is barely noticeable for the money/time it will cost.
Good stuff in this thread. I've been contemplating going down to 3.27's for a while now.
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