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Mad4Macs
12-12-2005, 03:33 PM
Meant to ask this earlier...

Those of us that have full-sized spares, have a front tire mounted in the trunk
(found out the hard way, I had a blow out this morning).
Given that we're also equipped with limited slip axles, does this make sense? I'm no expert, but it seems to me that having a spare rear tire would be more useful.
If you need a rear tire, and you've just thrown a front tire in back, wouldn't that cause problems for the differential?
Or, is it worse to have mounted one rear tire up front?
For me, it worked out ok, because I needed a front tire and I had a full sized spare, but it got me thinking... and thinking makes my head spin.
:lol:

TripleTransAm
12-12-2005, 03:49 PM
You are correct. It would make more sense to have a rear tire.

Why didn't they think of this, you ask? Because although they can bump up the MSRP of this car by $5000 for no reason, adding $30-$40 extra to the car's MSRP by including a bigger spare tire would be a no-no.

When you figure out the logic behind that one, let me know 'cause I can't figure it out either.

RF Overlord
12-12-2005, 04:40 PM
This is one of the exceedingly few times when I disagree with /Steve...I think having the front size as a spare makes sense (well, at least more sense than those foolish mini-spares). My reasoning is thus: having 2 differently-sized tires on the front might result in peculiar handling/braking during some crucial emergency-type manoeuvre, while having 2 differently-sized tires on the REAR may be somewhat less noticeable, hence "safer" for the average American driver, whom we all know is atrocious.

To answer Mad4Macs' second question: yes, it will play havoc with the Trak-Lok clutches. I read somewhere that Ford recommended not driving with the spare on the rear for more than (something like) 35 miles total. Maybe someone else can confirm this...

MENINBLK
12-12-2005, 04:56 PM
This is one of the exceedingly few times when I disagree with /Steve...I think having the front size as a spare makes sense (well, at least more sense than those foolish mini-spares). My reasoning is thus: having 2 differently-sized tires on the front might result in peculiar handling/braking during some crucial emergency-type manoeuvre, while having 2 differently-sized tires on the REAR may be somewhat less noticeable, hence "safer" for the average American driver, whom we all know is atrocious.

I gotta disagree with RF Overlord on this one.
When you are driing on your 'spare' you aren't
supposed to be driving like you stole it.

Petrograde
12-12-2005, 05:07 PM
funny this is mentioned.. I have a full sized polished spare (rear) in my trunk right. It's flat. :P

I'm glad I had a rear tire as a spare when I needed it,.. but I don't have a warm fuzzy about having a mismatched spare. If I get a flat in the front, I'm basically screwed.

You may be able to put a front on the back, but I don't think you can put a back tire on the front. ....Like RF said....

I guess I should buy another rim with a front tire... or put the same size on all four corners.

RF Overlord
12-12-2005, 06:06 PM
I gotta disagree with RF Overlord on this one.
When you are driing on your 'spare' you aren't
supposed to be driving like you stole it.As usual, Pete, you force me to clarify all my statements. :rolleyes:

The fictitious "emergency manoeuvre" I am referring to is not the kind caused by "driving like you stole it", rather I am referring to the unexpected kind, like when the weather suddenly turns foul and someone cuts you off...that sort of thing. I assumed most of the members of this board had enough common sense to understand that.

duhtroll
12-12-2005, 06:09 PM
I thought most blowouts were front tires due to running over stuff?

Statistically, that is. I've only ever had one, and I was told that fronts are the usual victims by the wrecker guy.

-A

SergntMac
12-12-2005, 06:36 PM
I examined this shortly after the doughnut spare became available in a 300B. I have resigned myself to believe that the full size spare is an outgrowth of several engineering oversights.

1) The OEM front brakes may be shared with many other Panther framed vehicles today (as we look back on the history of it all), but they were not so shared back in 2002, when the Marauder was released. Back then, no "doughnut spare" on the shelves to accomodate the early 2002 Marauder production. Likewise, no police steelies that clear our "Marauder-CV/PI-Town Car, 2003 and up" front brakes. No 18" doughnut wheels, no 18" doughnut tires to mount on them if we had them. Zip, zero, nada, nothing on hand from the parts bin, so, get busy on that. Meanwhile, we'll use a full size Marauder wheel and tire. This was the only choice for L/M when they decided to release the Marauder early, in June of 2002.

2) The wheel was available, but why spend the money to polish and clearcoat it? "It's just a spare, which may never see use anyway?"

NOTE: Yeah...My 1991 Gran Marquis with 88K miles, has a full size spare that has never touched the ground. Moreover, until I found it necessary in 2004, the OEM tool used to remove my wire wheel covers, remained sealed in it's OEM parts bag. Everyone needs to have a spare, not everyone needs to use them.

COMMENT: I am sure there is at least one Marauder owner registered here, that a) doesn't know he/she has a full size unpolished MM wheel with 235/55-18 rubber on it, and b) at least one Marauder owner here who will ask "WTF are you talking about?" That's how these thngs go.

3) When L/M calculated risk, the front tire size presents the lesser of two evils. A rear tire on the front will surely disrupt the ABS, and may cause a loss of control under unexpected hard braking, or, hard steering, during it's temporary role as a road tire. This risk is potential liability for L/M (Thanks, Bob!).

OTOH, a front tire on the rear may damage the LSD after extensive use, but that's just a repair and probably covered by warranty during the warranty period. You won't put the car into a ditch and sue L/M over that sales contract you lost because you missed that "once in a lifetime" luncheon, and when discussing warranty repairs to your TractionLok, your L/M service dude can peek at, and discuss all the mods you made to your own Marauder, and possibly escape that warranty liability too (Yes, I can be a tad paranoid at times).

CONCLUSION: The fug-ugly 300A full size spare in front tire size will allow safe operation of the car until the failed tire can be repaired, or, replaced. Actually, using the fug-ugly spare for any length of time is unthinkable to us, and it probably won't happen. There's no way in Hell any of us wish to be seen driving around on this fug-ugly spare long enough to damage the TractionLok diff to begin with. Repairs/replacement will be immediate, and we will creep through town via backroads and dimly lit side streets and alleys, or, rent cheap rooms on the fringe of any metropolitan city's darker side of town, just to not be seen on the public way, with one unpolished wheel on the car. Tell me I am wrong...

L/Ms message is "get it fixed soon" and I have no doubt that any of us, have not heard that message. If L/M knew our dispositions before they built the car, L/M knows how to deal with certain issues, and they have. We got the spare L/M wanted us to have, until an alternative was available. This was not part of "decontenting", just a "whew!" from L/M. But, I think they should have had some kind of "trade-in" thingy too, once the doughnut spare was available.

Just my .02C, gents, carry on...




WAIT! I almost forgot...

4) The rear tire properly inflated, and mounted on a Marauder wheel, polished or not, doesn't fit on the package shelf.

Ask me how I know...

Petrograde
12-12-2005, 07:10 PM
WAIT! I almost forgot...

4) The rear tire properly inflated, and mounted on a Marauder wheel, polished or not, doesn't fit on the package shelf.

Ask me how I know...

^This is a fact^ I pushed, and crammed,... and I couldn't get the damn locking bar,.. er wire,.. what the hell ever it is installed.

However, the rear tire inflated to 35 psi will fit snuggly in the bottom of the trunk. :P

TripleTransAm
12-12-2005, 07:10 PM
So what size does the mini-spare work out to, the equivalent of a front or rear?

Mad4Macs
12-12-2005, 07:58 PM
Funny it was mentioned that we wouldn't be caught driving with the unpolished wheel, because I sure didn't! The car went DIRECTLY to the shop, where I asked them to unmount the spare and install it on my polished wheel. I ordered a matching front for the other side, then moved the old (but still useable) tire onto the unpolished wheel.
And... yeah! Is the mini wheel the same size as the stock front? If it isn't, then Ford's sole decision seems to be one of "It wouldn't fit on the deck".
Dang... and all this time, I thought that engineers engineered cars.
I guess, more and more, that the Marauder's a mutt.
Good thing I like mutts!

:lol:

valleyman
12-12-2005, 09:37 PM
I have a 245/55 mounted on a polished rim as a spare and it fits on the package shelf in my trunk, i.e., in the spot where the spare came from the factory, using the OEM securing device. My MM is a 300A.

SergntMac
12-13-2005, 04:25 PM
I have a 245/55 mounted on a polished rim as a spare and it fits on the package shelf in my trunk, i.e., in the spot where the spare came from the factory, using the OEM securing device. My MM is a 300A. That's good for you, but I couldn't get mine up there to save my life. BTW, thought I should remind y'all that have a mini-spare, and a front brake upgrade, you're going to be S.O.L. if you get a flat in the front. The mini-spare won't fit with big brake kits like Baer. Best to check it out before you get stuck somewhere dark.

David Morton
12-14-2005, 06:44 AM
It makes sense to have a front-size spare for two reasons.

1) Yes, as duhtroll said it is a front tire that fails most often, so statistically it's a front tire you need most.

2) It's better if it is a front tire that goes flat to have a match for that tire as SergntMac explained, ABS goes ape***** and defaults with a different one there. Default = NO ABS!. Also this has no downside if it's a rear tire that blows. It can be used on the rear with NO damage to the limited slip differential as long as you don't go torqueing up the springs in the diff, or decide to go to Timbuktu. Drive it like grandma drives until you get to a service facility and obtain a new rear tire. It is a myth that having two different size tires on a limited slip axle will hurt it. It will heat up some, so don't go easing it up to 80 and cruise for 40 miles. Only if you accelerate hard enough to engage the clutches will you do anything to the clutches and this will just result in engaging them and giving you a rear-end induced twist that will feel like the front-end pulls, not to mention the wearing out of the tires back there. As long as you aren't torqueing up the diff, it will simply differentiate like it would if you were in a slow turn.

Besides, if you're so poor you can't afford to get a new tire the same day one dies, you shouldn't have bought this car in the first place. I have a doughnut spare to save weight and give me more room, plenty of room for a plugger kit for those roofing nails.

Mad4Macs
12-14-2005, 07:03 AM
Not sure why the comment about being "too poor" to buy a tire came up, but at least the question seems to have been answered. Never knew that the rear end was tolerant to different sized tires being installed, so I thought I'd ask.
Heck, I repair computers for a living, not cars :D
Anywayz... I took mine from "blow out" condition, to replacing both fronts (just to be safe), and did it within 2 hours and 5 miles.
I drive for a living, and the only thing I can't afford is downtime!
:lol:

merc6
12-14-2005, 07:12 AM
I had 3 snow tires and the 1 front stocker on (Remember my fun with studs thread) and car pulled a lil bit at highway speeds. Most of my driving is highway. once you reach a certain speed or distance brake and abs lights kick on till you turn car off. I still don't see how a small ass donut could be benefitial any. if you got a flat in the back you loose traction like a mofi if it's snowing.

Marauderman
12-14-2005, 10:09 AM
That's good for you, but I couldn't get mine up there to save my life. BTW, thought I should remind y'all that have a mini-spare, and a front brake upgrade, you're going to be S.O.L. if you get a flat in the front. The mini-spare won't fit with big brake kits like Baer. Best to check it out before you get stuck somewhere dark.
Add me to the list as is Valleyman.....cause I too have my OEM rear tire on polish rim on the rear shelf no problem--true --a little work --but there is a trick to it----which is to have a second person handy..

While placing the hook in the hub opening , do so with the tire at a angle off the shelf resting against your left forearm using your right hand for placing the hook inside to "hook" the bracket.....now since your "hands" are tied up...your second helper pushes the tire up onto the shelf and your right hand pulls up the hook for the bolt to thread down onto.....works for me.....Tom