Front Differential Chewed due to incorrect wheel/tire se up
#166
08-19-2011, 07:49 PM
i am now running a stock size 225/40/18 frt on slightly worn ps2's, and new 315/30/18 rears. since installing the new rears the abs/psm warning lights have thrown, but only once and have not yet returned after cycling ignition/overnight etc.
my question: does anyone have any experience with running the wider rear 315/30 with ( or without? ) issues. i realize i'd be better of upping the fronts to 235/40/18 but would like to at least wear out the existing tires without wearing out the front diff!
i've been told by more than a couple very knowledgeable people that i'm ok and within "spec" to run the sizes i am, but since i've gotten the dreaded psm/abs failure CEL, i'm really like to know if anyone has direct experience with this sizing issue. TIA.
my question: does anyone have any experience with running the wider rear 315/30 with ( or without? ) issues. i realize i'd be better of upping the fronts to 235/40/18 but would like to at least wear out the existing tires without wearing out the front diff!
i've been told by more than a couple very knowledgeable people that i'm ok and within "spec" to run the sizes i am, but since i've gotten the dreaded psm/abs failure CEL, i'm really like to know if anyone has direct experience with this sizing issue. TIA.
#167
08-19-2011, 08:11 PM
can i ( without risking potential front diff damage ) run the 225/40 front with 315/30/18's?? on stock twists ( although i'm switching soon to different wheels in same as stock size; 18x8 and 18x11 rears ).
someone else here has to have run this setup? the 315/30 is the gt2 rear size, while the 225/40/18 is the stock front sizing. again, if anyone is running or HAS run these sizes, i'd really like to know. thanks.
#168
08-19-2011, 08:39 PM
Hi Scott,
Based on those sizes, you have a mismatch in OD that could lead to a failure. Therefore, you need to select a new tire for either the front or the rear to get back into spec. Since you have a Pirelli Tire; theoretically you could run a 245/35/19. The OD of the Pirelli 295/30/19 is 26.1"; the OD of the Pirelli N1 Rosso 245/35/19 is 26.0". That will give you the proper OD matching.
HOWEVER... I cannot guaranty that running a 26" tire on the front will clear the front struts. If you are running OEM hardware on the front, I am fairly confident it will not clear. If you are running a coilover, it is likely that you can run a 245/35 no problem with clearance. It will likely rub the inner fender liner and turn lock though, depending on the ride height.
So... The cheaper way would be to replace the fronts with a 245/35/19 Pirelli, but IMO it would be a gamble on your car depending on your suspension setup. I wouldn't attempt it unless you have coilovers.
The other, more expensive option: purchase a 315/25/19 tire for the rear. Unfortunately, Pirelli does not offer that size. Therefore, you willl either need to purchase a complete set of tires, or run a mismatched set.
So...
Choice 1: purchase 245/35/19 (likely wont work with oem suspension)
Choice 2: purchase 315/25/19 rear tire (and possibly new set)
Hate to be the bearer of bad news on that.
Best of luck,
Chris
Based on those sizes, you have a mismatch in OD that could lead to a failure. Therefore, you need to select a new tire for either the front or the rear to get back into spec. Since you have a Pirelli Tire; theoretically you could run a 245/35/19. The OD of the Pirelli 295/30/19 is 26.1"; the OD of the Pirelli N1 Rosso 245/35/19 is 26.0". That will give you the proper OD matching.
HOWEVER... I cannot guaranty that running a 26" tire on the front will clear the front struts. If you are running OEM hardware on the front, I am fairly confident it will not clear. If you are running a coilover, it is likely that you can run a 245/35 no problem with clearance. It will likely rub the inner fender liner and turn lock though, depending on the ride height.
So... The cheaper way would be to replace the fronts with a 245/35/19 Pirelli, but IMO it would be a gamble on your car depending on your suspension setup. I wouldn't attempt it unless you have coilovers.
The other, more expensive option: purchase a 315/25/19 tire for the rear. Unfortunately, Pirelli does not offer that size. Therefore, you willl either need to purchase a complete set of tires, or run a mismatched set.
So...
Choice 1: purchase 245/35/19 (likely wont work with oem suspension)
Choice 2: purchase 315/25/19 rear tire (and possibly new set)
Hate to be the bearer of bad news on that.
Best of luck,
Chris
I appreciate it Chris... I spoke with the company that makes the wheels and they said the same thing... Sad but true...
You mentioned getting just rear tires... I thought on awd cars you have to replace all tires at the same time, regardless...
Thanks
Scott
#170
09-19-2011, 11:47 PM
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Location: Warwickshire, England
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i am now running a stock size 225/40/18 frt on slightly worn ps2's, and new 315/30/18 rears. since installing the new rears the abs/psm warning lights have thrown, but only once and have not yet returned after cycling ignition/overnight etc.
my question: does anyone have any experience with running the wider rear 315/30 with ( or without? ) issues. i realize i'd be better of upping the fronts to 235/40/18 but would like to at least wear out the existing tires without wearing out the front diff!
i've been told by more than a couple very knowledgeable people that i'm ok and within "spec" to run the sizes i am, but since i've gotten the dreaded psm/abs failure CEL, i'm really like to know if anyone has direct experience with this sizing issue. TIA.
my question: does anyone have any experience with running the wider rear 315/30 with ( or without? ) issues. i realize i'd be better of upping the fronts to 235/40/18 but would like to at least wear out the existing tires without wearing out the front diff!
i've been told by more than a couple very knowledgeable people that i'm ok and within "spec" to run the sizes i am, but since i've gotten the dreaded psm/abs failure CEL, i'm really like to know if anyone has direct experience with this sizing issue. TIA.
thanks, i'm sure that's optimum. but my question is:
can i ( without risking potential front diff damage ) run the 225/40 front with 315/30/18's?? on stock twists ( although i'm switching soon to different wheels in same as stock size; 18x8 and 18x11 rears ).
someone else here has to have run this setup? the 315/30 is the gt2 rear size, while the 225/40/18 is the stock front sizing. again, if anyone is running or HAS run these sizes, i'd really like to know. thanks.
can i ( without risking potential front diff damage ) run the 225/40 front with 315/30/18's?? on stock twists ( although i'm switching soon to different wheels in same as stock size; 18x8 and 18x11 rears ).
someone else here has to have run this setup? the 315/30 is the gt2 rear size, while the 225/40/18 is the stock front sizing. again, if anyone is running or HAS run these sizes, i'd really like to know. thanks.
I'd like to know this too
Last time I replaced my tyres I had all four done and they were OEM spec
It's now time for me to replace my rears (fronts are fine)
I can get an amazing deal on some 315's
But before I buy them I want to make sure it's safe to do so
Can I run my partially worn 225s with new 315s without causing any issues?
#171
09-20-2011, 03:03 PM
I'd like to know this too
Last time I replaced my tyres I had all four done and they were OEM spec
It's now time for me to replace my rears (fronts are fine)
I can get an amazing deal on some 315's
But before I buy them I want to make sure it's safe to do so
Can I run my partially worn 225s with new 315s without causing any issues?
Last time I replaced my tyres I had all four done and they were OEM spec
It's now time for me to replace my rears (fronts are fine)
I can get an amazing deal on some 315's
But before I buy them I want to make sure it's safe to do so
Can I run my partially worn 225s with new 315s without causing any issues?
i feel confident that all the advice i sought here and real world that running the 225/40 front 315/30 rear combo, while possibly not as desirable as running a 235/40 front, is in fact well within oem recommended spec and will not cause undue front differential wear issues. i hope your mileage won't vary, and believe you'll be fine.
Last edited by '02996ttx50; 09-20-2011 at 03:06 PM.
#172
09-20-2011, 03:15 PM
i am now running a stock size 225/40/18 frt on slightly worn ps2's, and new 315/30/18 rears. since installing the new rears the abs/psm warning lights have thrown, but only once and have not yet returned after cycling ignition/overnight etc.
my question: does anyone have any experience with running the wider rear 315/30 with ( or without? ) issues. i realize i'd be better of upping the fronts to 235/40/18 but would like to at least wear out the existing tires without wearing out the front diff!
i've been told by more than a couple very knowledgeable people that i'm ok and within "spec" to run the sizes i am, but since i've gotten the dreaded psm/abs failure CEL, i'm really like to know if anyone has direct experience with this sizing issue. TIA.
my question: does anyone have any experience with running the wider rear 315/30 with ( or without? ) issues. i realize i'd be better of upping the fronts to 235/40/18 but would like to at least wear out the existing tires without wearing out the front diff!
i've been told by more than a couple very knowledgeable people that i'm ok and within "spec" to run the sizes i am, but since i've gotten the dreaded psm/abs failure CEL, i'm really like to know if anyone has direct experience with this sizing issue. TIA.
#173
09-20-2011, 03:30 PM
thanks .. i'm within .4 in. sizing differential frt-rear now and feel good with this setup. i think it's now ant8u, that is struggling with the question! your experience also is good to hear..thx again.
#174
09-21-2011, 01:07 AM
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This is the ONLY post I remember seeing about this topic in over 6 years of visiting this site almost daily. This post has induced a lot of anxiety on this forum.
I'm not advocating risking your viscous coupling (not the front diff as has been suggested) but I think this whole issue may be a bit overblown. Worst case scenario is you pick up a used dime a dozen viscous coupling for $250... There are lots sitting around from all the RWD conversions.
Just keep the front/rear diameters within 1-2% or and you'll be fine.
I'm currently running 315/30-18 rear and 265/35-18 fronts on 12" and 9.5" rims with no issues (except for jealous stares for a seriously tucked look and virtually no under-steer
). These tires are .4" and .7" taller than stock front/rear.
Did I say these hankook RS tires are bad a$$?
I'm not advocating risking your viscous coupling (not the front diff as has been suggested) but I think this whole issue may be a bit overblown. Worst case scenario is you pick up a used dime a dozen viscous coupling for $250... There are lots sitting around from all the RWD conversions.
Just keep the front/rear diameters within 1-2% or and you'll be fine.
I'm currently running 315/30-18 rear and 265/35-18 fronts on 12" and 9.5" rims with no issues (except for jealous stares for a seriously tucked look and virtually no under-steer
). These tires are .4" and .7" taller than stock front/rear.Did I say these hankook RS tires are bad a$$?
Last edited by Turbo Fanatic; 09-21-2011 at 01:20 AM.
#175
09-21-2011, 06:08 AM
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Location: Warwickshire, England
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Thanks Guys
I've got a company offering 315 Pilot Sports at almost half price right now
I was unsure whether to go for them or not though as my fronts are 225 Conti's
I've got a company offering 315 Pilot Sports at almost half price right now
I was unsure whether to go for them or not though as my fronts are 225 Conti's
#176
09-21-2011, 09:51 AM
Share the wealth, what company? Hopefully not the scammer outfit in Vegas that advertises the 315/25/19 ps2 for about $300.
#178
09-21-2011, 07:06 PM
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Join Date: Jul 2008
Location: Warwickshire, England
Age: 41
Posts: 1,751
Rep Power: 140 Yeah, sorry, I'm in England........along with the wind and the rain
There's a company here with a web offer at the moment
Pilot sports in sizing 315/30/18 at around £140 each!
They usually go for £300+ all day long over here
#179
04-11-2012, 09:27 PM
Bump to an old thread. I want to buy a set of tires and I'm wondering if this will work.
235/35/19 Overall Diameter 649mm
295/30/19 Overall Diameter 663mm
I was told by the seller that the difference in height is within the safe zone.
Any help?
235/35/19 Overall Diameter 649mm
295/30/19 Overall Diameter 663mm
I was told by the seller that the difference in height is within the safe zone.
Any help?
#180
04-24-2012, 06:11 PM
bringing this old thread back...On my way to Vegas last week my front diff blew out. Had it towed to the dealer in Albuquerque. The car had about 33k miles on 235/35/19 and 305/30/19. This thread is all I found while searching for this issue. The dealership said it's extremely rare for these front diffs to fail.