With stock gears and 35's, what causes the transmission to crap out? Is it mainly from overheating or do the 35's just add that much stress to the transmission? Can adding a shift kit and an extra cooler prevent slippage? Also, about how long would you expect the transmission to last on stock gears before needing new gears and a new transmission? I've been wondering about this for a while, so any input is appreciated.

 

It helps to know what gears you have.

 

Should've added that. My bad. 3.73's

 

My buddy had 35's on his 4.0 3.73 '98 truck with a rebuilt auto trans. That trans went **** up in under 15,000 miles after being lifted.


Any other size tire would be fine...but when you start getting into 35's, you really really need to start considering a gear swap. What goes **** up is the heat build of the fluid in the trans because it's being pushed so hard....fluid temps. Clutches and more wear on the torque converter too. Plus, the added weight of the tires you're turning comes into play too, not just the diameter. Not to mention the absolutely horrible driveability.

4.10's can get away with it better and last alot longer.....but IMO...still holds true....start getting into 35's, gear swap needs to be considered.

 

gospel brother. gospel. its abig part holding me back from 35's

 

Is that the red truck with the 01+ swap and whatnot?

 

Yeah.....Austin's '98 on 18's and grapplers. That tranny going out birthed a manual trans swap which drove even worse than with the auto because it's a manual after all....you're alot more personal with the truck. Lots of clutch slippige to get it moving and/or lugging the heck out of the engine to get it moving. Me gearing mine to 4.88 birthed a 4.10 axle swap. My old rear axle's crosspin snapping in half and grinading the ring & pinion gear birthed a 4.88 installation.

 

I read through Trepauls auto to manual swap and that seems like a pain in the ***. So I "could" get away with 4.10's and 35's? What's about the average going price on an axle with 4.10's? All the junkyards around me are bonkers with prices but most will price match. A shift kit wouldn't help with the transmission going out though would it?

 

4.10s and 35s is still going to blow. Forget about the shift kit and just re-gear the damn thing. It's not worth the time and money to swap to 4.10 axles and still be very under geared.
My 97 explorer had a 4.0L OHV, auto, 4x4 with 3.73s and 31s and it was a dog.
My 98 ranger had a 4.0L OHV, manual, 4x4 with 3.73s and 33s and it was a kind of a dog.
Either way I would not run 35s and 4.10s. You're asking for trouble still and a shift kit is a short term band aid. The drivetrain is still going to have to work a lot harder and wear out much faster.

 

I was still planning on a re-gear, just curious what the life expectancy of the transmission would be in case funds weren't immediately available

 

Heat and over working makes the trans crap out. To answer your question

 

YES.. Your tranny will Implode. ok, well maybe not that dramatic, but your tranny will take a shat. AT the VERY LEAST you should go with 4.56 thats what i put in my ol' ranger(00) and it ran pretty good.. Some days i wanted to go to 4.88's but i drove on the highway too much.. If you do alot of driving go with the 4.56 if not go 4.88

 

I have quite the opposite opinion....

 

Really? I was always told that 4.56's are better on the freeway than the 4.88's.. atleast thats what ya'll told me when i was asking about it hahaha

Go with what he says.. he is much smarter than I when it comes to this stuff..

 

just curious what are the "Danger" temps for a tranny?

 

i run an auto 3.0l 08' ranger with 32" tires and 4.10 gear. i had the trans rebuilt at 60,000 for a transfercase instal. the only things that were noticed was a couple burnt clutches and a band was well worn, but if you can budget and keep up on the maintenance of the trans then the trans wont be junk to quickly, you may need to do more frequent fluid flushes and possibly a rebuild every so many 1000 miles. a shift kit will help with some shift pressures, the ford trannies are very prone to blow outs or cracks in the valve bodies do to high shift pressures. for 35"-36" tires, i plan to drop to a 4.88 for my gear since ive seen the damage of larger tires. and also when driving, i try to take it easy on acceleration, because the trans will only slip and burn clutches when your hot on the throttle..