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robert
03-16-2003, 12:49 PM
hello,

from this question you will all know that i do not have a mm. the question is, what is the tire size of the spare tire in the marauder? since the front tires are smaller than the rear tires, if the spare is the same size as the front tires, would IT damage the limited slip if two different size tires are mounted on the rear axle should a flat occur?

robert

vaderv
03-16-2003, 01:17 PM
its only reccomended for 50 miles if used on the rear.

RF Overlord
03-16-2003, 01:20 PM
Robert:

The 300A has a full-size spare that is indeed a "front" tire, and yes, if left on the back with a "rear"-size tire, it will damage the Traction Lok. It is only to be used for as short a time as possible...

The 300B come with a mini-spare, I don't know what the limitations are on that...

martyo
03-16-2003, 05:48 PM
RF: The limitation is to call a flat bed! I wouldn't drive more than a couple of miles with the dognut spare on the rear.

robert
03-16-2003, 07:42 PM
thanks for the reply everyone. my vic has 255/50/16 for the summer. it has 225/60/16 for the winter. there is a slight difference in the overall diameter. my summer ones are a bit smaller. i want to carry, as a spare, 225/60/16. what do you all think of this?

thanks

SergntMac
03-16-2003, 09:17 PM
Originally posted by robert
my vic has 255/50/16 for the summer. it has 225/60/16 for the winter. there is a slight difference in the overall diameter. my summer ones are a bit smaller. i want to carry, as a spare, 225/60/16. what do you all think of this? thanks

To be totally honest here, robert, and true to my word given in other threads here, "if it ain't a Mercury Marauder, I don't know."

And, I don't know if anyone else here would know, how to answer your question.

Kinda makes me wonder why you would ask us here...

RCSignals
03-17-2003, 01:05 AM
Robert, I think it would be fine if you carried that as a spare.
Because it will be different size from your summer tires, only use it as a spare, obviously.
Unless you put trac-loc on yourself, or you have a PI that has it, your CV won't have trac-loc from the factory so that won't be a consideration

robert
03-17-2003, 07:49 PM
Originally posted by RCSignals
Robert, I think it would be fine if you carried that as a spare.
Because it will be different size from your summer tires, only use it as a spare, obviously.
Unless you put trac-loc on yourself, or you have a PI that has it, your CV won't have trac-loc from the factory so that won't be a consideration

rcsignals, i do have frpp traction lok with 3.55. i put them in. would it be safe to use two different size tires on the rear axle?

LincMercLover
03-17-2003, 09:03 PM
Not for extended driving periods no. With the difference in size and turning ratio, it can damage the locking devices of a rear end, rendering the whole set-up trash. Only go a short distance (25 miles tops I'd say) at slower speeds, taking special care around turns. Granted, it's a "spare," but only a temporary one.

SergntMac
03-17-2003, 11:13 PM
Originally posted by robert
rcsignals, i do have frpp traction lok with 3.55. i put them in. would it be safe to use two different size tires on the rear axle?

Ummm...Nevermind.

I've given the Moderators enough work as it is.

robert
03-18-2003, 08:44 PM
Originally posted by LincMercLover
Not for extended driving periods no. With the difference in size and turning ratio, it can damage the locking devices of a rear end, rendering the whole set-up trash. Only go a short distance (25 miles tops I'd say) at slower speeds, taking special care around turns. Granted, it's a "spare," but only a temporary one.

lincmerclover, thanks for your answer. will do.

Warpath
03-19-2003, 10:30 AM
I think "damage" is too strong a word. With different size tires, the clutch packs of the traction lock would wear out quicker. Once the clutch packs wear out, it acts like an open diff. I have/had traction lock on several trucks now and haven't had the packs last more than 15k miles anyway. I believe the clutches can be replaced separately. I've never tried it myself.

RF Overlord
03-19-2003, 11:22 AM
Originally posted by Warpath
I think "damage" is too strong a word. With different size tires, the clutch packs of the traction lock would wear out quicker. Once the clutch packs wear out, it acts like an open diff.

War, that pretty well sounds like "damage" to me; my Traction-Lok will no longer work as intended...sure, the car is still drivable, but I've lost an important feature, one that is probably fairly expensive to fix...better to not let it happen in the first place.

LincMercLover
03-19-2003, 12:11 PM
If seen them so much as begin to "chew" up teeth in there from this clutch "damage." Baisic rule of thumb, if it has an axle, then keep the tires the same size.

Warpath
03-20-2003, 09:36 AM
I guess I think differently than most. Depending on how you perceive it, damaging the traction lock could be interpreted as an inoperative vehicle. The clutches can be completely worn and the vehicle would still drive the same minus the traction lock feature. Its kinda like saying using the clutch in a manual trans or using the brakes will damage them since you wear out the clutch or brake pads. They're consumable parts. I've never heard of worn clutches damaging the gears. Sounds like something else was wrong too. But, like LML stated, keep the tires the same size.

SergntMac
03-20-2003, 03:16 PM
Originally posted by LincMercLover
If seen them so much as begin to "chew" up teeth in there from this clutch "damage." Baisic rule of thumb, if it has an axle, then keep the tires the same size.

This would be my position too, if I were to post an opinion on this topic.

My "posi" experience is rather stale, I grew up on the General's 68-70 12 bolt, in 4:11, 4:56, 4:88, and 5:13 flavors. It was very true back then, that the tire size was extremely critical to the health of a GM positraction unit. Tires were bias ply, almost perfectly 45 degrees square with the pavement. there were a few "wide ovals" showing up, but that was a "radical" departure from the common think of the era.

However, that was 40 some years ago, and things were not as refined as they are today. Tire size was so critical, that even unmatched tire pressure under power, could blow a posi unit. Gear mashing and chewed up teeth? Oh, you bet, big time. Didn't just break, in like stop working, but broke broke, as in busted, mashed, twisted, and if you were unfortunate enough, exploding, blow up the banjo housing, twist axels like pretzels, and pop u-joints. Graphic enough for you?

If I were to post an opinion on this topic, I would suppose things are much...ah...better these days, eh?

TripleTransAm
03-23-2003, 07:05 PM
Originally posted by Warpath
I've never heard of worn clutches damaging the gears.


I'd be inclined to think that it's due to the excessive 'use' of the small 'inner gears' (I honestly can't remember what they're called). These small gears ride on a carrier that is driven by the pinion gear. If both axles are rotating at exactly the same speed, these small gears should not be turning, instead delivering power to both axles. If the axle speeds differ, the little gears will rotate in their own shafts, relative to the axle speed differences, as they push the axles. I suppose constant axle speed differences would result in increased wear for these little buggers. With a non-locking or non-limited-slip diff, these little gears spin at their maximum, as one axle is completely stopped... the little gears have to spin wildly to be able to deliver the power to the rotating axle. In other words, the little gears 'walk' on the stopped axle's gear teeth, and spin the moving axle at a greater speed.

And come to think of it, clutch material has to end up in the diff fluid as the clutches wear... this means the lubricating action of the diff fluid is decreased and might actually lead to dramatically increased gear face wear!

Warpath
03-24-2003, 09:50 AM
Originally posted by SergntMac
However, that was 40 some years ago, and things were not as refined as they are today. Tire size was so critical, that even unmatched tire pressure under power, could blow a posi unit. Gear mashing and chewed up teeth? Oh, you bet, big time. Didn't just break, in like stop working, but broke broke, as in busted, mashed, twisted, and if you were unfortunate enough, exploding, blow up the banjo housing, twist axels like pretzels, and pop u-joints. Graphic enough for you?


Well, I learn something new everyday. Still though, I haven't had these things last more than 15k miles. No problems with gears after they have worn. That's just my experience though.

SergntMac
03-25-2003, 07:30 AM
Originally posted by Warpath
Well, I learn something new everyday. Still though, I haven't had these things last more than 15k miles. No problems with gears after they have worn. That's just my experience though.

Well...that was 40 some years ago, when (for a few years) one could stroll into any new car dealership and drive out with 425 plus ponies, and straight into a race. Add to that, most of us were still kids too, and prone to pushing things blindly forward, only to discover the weaknesses of other powertrain components. Stuff blew up, often. One friend of mine owned a '70 hemi 'Cuda, and he would change U-joints with his oil, needed or not. Yup, things are greatly improved today, and longevity has been added to the vocabulary. However, likewise threats remain constant. As some of us here explore supercharging, or, juice, weaknesses will rise to their calling.

The chief question here, was if unmatched tire sizes could cause damage to a posi, or, limited slip unit. I think the answer to that is clearly yes.

LincMercLover
03-25-2003, 08:04 AM
Ahh yes. The U-joint/oil change. I remember those with my Dad's 1968 Road Runner. The now THAT was Detroit power, or :censor: U-joint design... Nah... I think it was the first one. :D