After tomorrow................
- Thread starter Cman01
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How do you like the 4.10s? What tire?
Tony:
If you give up on the special 3.90s just go FRPP 4.10s
Car is SO much better with a gear.
I spent several hours debating 4.11s or 3.89s for the Strange 9", I laughed when I looked up all the options and they listed a new 4.0 ratio, so much for all that math, just hit the easy button and went 4.0
-J
No, not giving up on the 3:90's yet J, didn't hear anything back the last couple days so I'll wait till later in the week for an update (if there is one), but other than the noise for me this ratio rocks!!! (It's perfect for what I wanted no need for 4:10's here).
So you chose a 4.00 gear for your 9"? Sounds good but I wonder about something. I had read stuff way back that gear ratios are usually some weird odd # so that the same teeth on the ring and pinion don't always make contact every revolution or so with each other. It has something to do with wear so that each ring and pinion teeth will always contact a different teeth on that gear during every rotation.
A 4:1 ratio gear set will mean 1 pinion teeth will always contact the same ring gear teeth every 4 revolutions. It may wear more than say a 3.73:1 R&P (every 3:73 revolutions of that gear set the same pinion tooth will not contact the same ring gear tooth so it will take many revolutions of the gear set before the same tooth on the R&P will contact each other, basically giving all the teeth on the pinion to at least make contact with all the teeth on the ring gear every few revolutions and helps with wear).
Just something to wonder about.
So you chose a 4.00 gear for your 9"? Sounds good but I wonder about something. I had read stuff way back that gear ratios are usually some weird odd # so that the same teeth on the ring and pinion don't always make contact every revolution or so with each other. It has something to do with wear so that each ring and pinion teeth will always contact a different teeth on that gear during every rotation.
A 4:1 ratio gear set will mean 1 pinion teeth will always contact the same ring gear teeth every 4 revolutions. It may wear more than say a 3.73:1 R&P (every 3:73 revolutions of that gear set the same pinion tooth will not contact the same ring gear tooth so it will take many revolutions of the gear set before the same tooth on the R&P will contact each other, basically giving all the teeth on the pinion to at least make contact with all the teeth on the ring gear every few revolutions and helps with wear).
Just something to wonder about.
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How do you like the 4.10s? What tire?
Tony:
If you give up on the special 3.90s just go FRPP 4.10s
Car is SO much better with a gear.
I spent several hours debating 4.11s or 3.89s for the Strange 9", I laughed when I looked up all the options and they listed a new 4.0 ratio, so much for all that math, just hit the easy button and went 4.0
-J
The 4.10s are great. Like I said it really depends on installer to get them not to whine. I went to Tampa this weekend to break them in on the highway at got 19.7mpg with the cruise control set at 80mph!
On Street I Run 285/35r20 Pilot Sport 4S.
Track I run 29x11.50r15 Hoosier QTPs. Results pending at track! Way too hot in Florida to get any real results right now.
-Pierce
New update: US Gear called and spoke to the shop yesterday and the owner contacted me with the news.
US Gear wants him to adjust the pattern on the gear set and will cover the labour for him to do that, afterwards we will see if the noise is way reduced or eliminated all together. If it's good, we're good. If not US Gear will send another gearset for him to install according to their instructions and again will cover his labour to do that also OR if after the adjustment the noise is still there I can opt for them to reimburse me the cost of the gear that I have in the car already.
I really don't want cash back and have to live with a noisy gear so I hope the adjustment will sort this out or another gearset.
Now I have to arrange to go back up there again to have the gear pattern adjusted, probably next week sometime I'll go back there for him to do it.
US Gear wants him to adjust the pattern on the gear set and will cover the labour for him to do that, afterwards we will see if the noise is way reduced or eliminated all together. If it's good, we're good. If not US Gear will send another gearset for him to install according to their instructions and again will cover his labour to do that also OR if after the adjustment the noise is still there I can opt for them to reimburse me the cost of the gear that I have in the car already.
I really don't want cash back and have to live with a noisy gear so I hope the adjustment will sort this out or another gearset.
Now I have to arrange to go back up there again to have the gear pattern adjusted, probably next week sometime I'll go back there for him to do it.
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Interested in the results and what they want changed. I've swapped in a 13/14 transmission and have 3.73s, but with my cam, I'd like a little more revs at highway cruise. This might not be a bad set to get as they seem to stand behind their product.
I didn't get exact details from the shop but US Gear people saw my gear pattern and told the shop to adjust it slightly and see if the noise is better. When I go back there again I'll get better details about it.
Just remember I don't have a regular 3:90 gear set from them I have their ISF Lightning Gear set.
Ford 8.8
Just remember I don't have a regular 3:90 gear set from them I have their ISF Lightning Gear set.
Ford 8.8
I'm keeping a close eye here, hoping to hear something good come out of this!
Glad to hear US Gear's is taking care of you and your not having to fork out more money for service. I think things like this speak volumes about a brands loyalty and customer service!
Yes, I do like the fact that they will look after this by paying the labour and/or a new gearset.
In reality, I hope the adjustment will fix the noise. This will be my second trip back there to the other end of the city I really don't want to make a 3rd trip if the adjustment doesn't fix it but if it means another install with a BRAND NEW gearset...…………………..gotta do it.
In reality, I hope the adjustment will fix the noise. This will be my second trip back there to the other end of the city I really don't want to make a 3rd trip if the adjustment doesn't fix it but if it means another install with a BRAND NEW gearset...…………………..gotta do it.
Got a question guys, after the initial gear install I refilled with the proper Ford gear oil 75W85. I'm wondering if using a thicker gear oil with the Torsen might help with reducing the noise I have.
I looked up Amsoil's site and specified for the Shelby is their 75W90 gear oil with a footnote to actually use the Ford oil that I'm using (basically thinking of using a thicker gear oil just got thrown out the window).
I know some guys have used a different viscosity gear oil when they did gears (and other model Mustangs use 75W140 gear oil in their diffs).
I want to make sure whatever I use doesn't mess up the function of the Torsen diff also.
Tony
I looked up Amsoil's site and specified for the Shelby is their 75W90 gear oil with a footnote to actually use the Ford oil that I'm using (basically thinking of using a thicker gear oil just got thrown out the window).
I know some guys have used a different viscosity gear oil when they did gears (and other model Mustangs use 75W140 gear oil in their diffs).
I want to make sure whatever I use doesn't mess up the function of the Torsen diff also.
Tony
FWIW, the '02-05 Ford Explorers with the limited slips had a common issue with whining diffs. They called for 75W90 like you mentioned, but filling up with 75W140 actually reduced the whining quite a bit. I did exactly that and it made a noticeable difference. I think you just need to be mindful to use fluid that has additives for limited slips.
With the higher torque multiplication of the lower gears, it's probably a better idea to run the heavier oil. I'd probably use a mineral based oil instead of a synthetic to expedite break in.
Got the gear adjusted. The pattern was moved slightly towards the heel of the gear teeth and backlash increased to 0.015".
Did it help???? Well yes and no. The noise is reduced slightly during cruise around 35-45mph but I don't feel too much difference on the highway cruising at my normal 70-75mph. Again just holding the speed there (install guy calls it "floating the gear" and the constant ringing is there again), and lightly stepping on the throttle or backing off from that speed and no noise. Sometimes it feels like I can feather the throttle at that speed just enough where the noise is less but it is not like before with the stock 3:31 gear.
So now what to do??? He placed a call to the person he's been speaking to from US Gear to see what they want to do (they will get copies of the above pics for them to see).
I'm not sure what I want to do...………..can I take a chance on the 3rd try with perhaps a new gearset supplied by US Gear or take the money from them for this gearset and maybe buy a Motive 3:90 and try again??
I paid the shop this time for the initial install, they didn't charge me for the adjustment and will not charge me again for a new US Gear install if they supply it. If I go Motive I would obviously have to pay him again for that install.
I'm very disappointed with the outcome of this gearset, granted I'm glad that they are going through the effort it looks like to sort out this problem but the whole point I went with the ISF gearset was to avoid these issues and this is a total fail. I probably would've had better luck doing a regular gearset.
I will hear from the shop probably in the next few days after the weekend on what US Gear will do, as of right now I have the green light from them to let it rip and I plan on doing that (no more grandma driving in my Shelby), who knows...………….beating on it a bit might help it wear in better and reduce the noise.
Did it help???? Well yes and no. The noise is reduced slightly during cruise around 35-45mph but I don't feel too much difference on the highway cruising at my normal 70-75mph. Again just holding the speed there (install guy calls it "floating the gear" and the constant ringing is there again), and lightly stepping on the throttle or backing off from that speed and no noise. Sometimes it feels like I can feather the throttle at that speed just enough where the noise is less but it is not like before with the stock 3:31 gear.
So now what to do??? He placed a call to the person he's been speaking to from US Gear to see what they want to do (they will get copies of the above pics for them to see).
I'm not sure what I want to do...………..can I take a chance on the 3rd try with perhaps a new gearset supplied by US Gear or take the money from them for this gearset and maybe buy a Motive 3:90 and try again??
I paid the shop this time for the initial install, they didn't charge me for the adjustment and will not charge me again for a new US Gear install if they supply it. If I go Motive I would obviously have to pay him again for that install.
I'm very disappointed with the outcome of this gearset, granted I'm glad that they are going through the effort it looks like to sort out this problem but the whole point I went with the ISF gearset was to avoid these issues and this is a total fail. I probably would've had better luck doing a regular gearset.
I will hear from the shop probably in the next few days after the weekend on what US Gear will do, as of right now I have the green light from them to let it rip and I plan on doing that (no more grandma driving in my Shelby), who knows...………….beating on it a bit might help it wear in better and reduce the noise.
Man, I dont know what I would do. I dont think its the gearset itself.
It would be interesting to see the % of owners who upgraded Gears and didnt have some whine afterwards?
Ive just learned to live with mine, roll down the windows and crank up the music.
Mine is similar to yours in that it whines mainly in 6th gear when letting off/on the Gas and keeping speed at a constant.
Good luck in the decision you pursue and keep us posted on the results.
It would be interesting to see the % of owners who upgraded Gears and didnt have some whine afterwards?
Ive just learned to live with mine, roll down the windows and crank up the music.
Mine is similar to yours in that it whines mainly in 6th gear when letting off/on the Gas and keeping speed at a constant.
Good luck in the decision you pursue and keep us posted on the results.
I put ford racing 410s on mine twice with the same result I have a friend that works for ford and he let me borrow the tools the ford book calls for but it does the same thing at highway cruising speed, I said f it and drove it I’m oblivious to it now with loud exhaust and music haha but I have all spherical bmr suspension and welded axle tubes so idk if that makes the noise worse I would think it does as there is no longer rubber at them point of contact, good luck
It's the gear. The larger the gear set, the greater the whine. It's partially the cut of the gear and partially the harmonics.
I have had a number of gears in my car over the years and without question, the worst was 390s. Outstanding installers including the guy that builds and sets up rears for the Cobra Jet and the COPO.
Regardless of how perfect it is (we found 012 to be the sweet spot on my car btw), one hard launch and they'll be singing again.
Been this way with TruTrac, WaveTrac (P. O. S.) and a spool.
Ford gears are cut differently and offer the best results. Still not "quiet"
Sent from my SM-N950U using Tapatalk
I have had a number of gears in my car over the years and without question, the worst was 390s. Outstanding installers including the guy that builds and sets up rears for the Cobra Jet and the COPO.
Regardless of how perfect it is (we found 012 to be the sweet spot on my car btw), one hard launch and they'll be singing again.
Been this way with TruTrac, WaveTrac (P. O. S.) and a spool.
Ford gears are cut differently and offer the best results. Still not "quiet"
Sent from my SM-N950U using Tapatalk
BJ,
What affect do the axle dampeners have on the harmonics?
What affect do the axle dampeners have on the harmonics?
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