issues with clutch and taller tires

[irishpilot]

Hi,

I bought my brothers explorer, its a 91' 4.0 4x4 5spd.
It has a new clutch less than 6mo old, clutch was bought from napa and was a new unit, not a reman. we installed it as well as a new slave cylinder.

my issue is he bought more agressive tires the size is 235/75/15, and the truck has a hard time with starting from a stop. it feels like the tranny gearing is too much for the engine to handle. it putters along until I get the revs to about 2k between shifts, then it feels as it should right after a normal shift.

I am going to do the MAF cleanup, because i do feel a little hesitation in the motor, but is it the tires that is causing this issue?

I've owned a ranger before and it was geared way to tall as well... is this a ford thing?

 

[MrShorty]

What differential gear ratio do you have?

235/75 15 is essentially the stock tire size. I run 31" tires with a 3.73 gear ratio and it pulls just fine. Is the clutch slipping or is the engine just not pulling?

 

[irishpilot]

when I try to rev the engine high and then let the clutch out it slips.
I dont know what the diff ratio is...if I got the vin could i find out that way?

thanks

 

[MrShorty]

Probably, but it's easier to look at the sticker on the door jamb and cross reference the axle code to the several lists posted on the internet, or to read the ratio off of tag bolted to the rear differential cover.

The clutch is slipping?? That doesn't bode well for Napa's clutch. Did the clutch ever function correctly?

 

[irishpilot]

ya, it functions pretty good I would say.

I found a ranger site with those numbers, I will see what it is.

 

[Jason94sport]

Those are stock size tires, so they are not the problem.

 

[irishpilot]

my diff ratio is 3.55

it that a taller gear?
how hard would it be to change it to the next lower gear?

 

[Con Seann3ry]

3.55 should be fine for those tires, I'd look for the problem elsewhere

(regearing is expensive)

 

[monkeydude3]

I've got a 1994 XL explorer with a lifetime warranty clutch from autozone... works grand if I do say so myself. 2k rpm is my average shift point when I'm going for economy (i laugh at that word, economy, though with an Explorer ) I'd say just do a general overall tuneup for a 1991. Plugs, wires, etc... fuel system clean, new fuel filter, all the basics that can't hurt. See if that helps. It helped mine when mine acted like that. It sounds like yours just needs a tuneup

George

 

[irishpilot]

It just had a tuneup, but my brother said that the dizzy cap and rotor wasn't replaced plus I am going to do that MAF cleanup.

would you guys with 5spd's say that they are a geared a little to high? Its just I cant imagine this pulling my boat with how high its geared.

 

[LOGJOCKY]

NAPA has really crappy clutches from my experiances

 

[irishpilot]

is there such thing as adjusting the clutch in the explorer's, could that help?

 

[JDraper]

It just had a tuneup, but my brother said that the dizzy cap and rotor wasn't replaced plus I am going to do that MAF cleanup.

would you guys with 5spd's say that they are a geared a little to high? Its just I cant imagine this pulling my boat with how high its geared.

First off, there is no distributor cap and rotor in the Explorer. It's a distributorless ignition. Secondly, 235/75R15 is the stock tire size. You should have absolutely no problem with your clutch because of the tire size. I'd look somewhere else, like a bad clutch or pressure plate. If you didn't either re-face or replace the flywheel when you replaced the clutch and pressure plate, you may have ruined the new clutch too.

As for towing, I used to tow a 26' camper behind my '92 Sport (3.27 gears) with the 5-Speed with no problems.

 

[MrShorty]

is there such thing as adjusting the clutch in the explorer's, could that help?

Clutch is purely hyudraulic, and doesn't require adjustment. It does require bleeding and to have a good supply of fluid.

 

[irishpilot]

If there is any air in the clutch line would that cause the clutch to act any differently when the clutch is depressed? I would think not, but we did have a hard time getting the the slave cylinder to actually build pressure. I actually followed a writeup on this site for doing the clutch.

Jdraper- We didn't get the flywheel resurfaced because it looked fine, no gloss or anything. we got a heavy grit sandpaper and gave it a good go around just to make sure though. I hope thats not the issue cause I dont want to have to take it all out again

 

[JDraper]

Flywheel glazing is only one of the reasons to get the flywheel resurfaced. Warpage can also cause clutch failure.

Is it possible that the motor or tranny is leaking and putting fluid on the flywheel? That would cause slippage.

 

[irishpilot]

I'll check for any leaks, would they need to be directly at the bell housing?