Reverse Question

[Grudge855]

Hey guys, I'm new to the forum and to the KJ and I'm loving both. Tons of great threads here, I'm definitely learning a ton from this site. However, I have noticed one strange thing with my KJ. It seems to struggle when I have it in reverse. It creeps very very slowly when the wheel is only slightly turned (half turn-ish) and by the time you have the wheel turned completely to one side the jeep is barely moving. Backing up the driveway is even worse. The driveway is sloped but only slightly and the Jeep will not go up it without giving it gas (more than you would expect for such a small slope) and I'm afraid of giving it too much gas, I'd rather not have the Jeep end up in the kitchen. My previous car (99 Neon) and my father's car (93 Lumina) were/are able to back up the driveway just fine without using the accelerator.

My Aunt's KJ has the same problem so I'm guessing it's a common thing. Is there any way of stopping this problem? Or at least make the reverse work somewhat better?

I searched the forums and wasn't able to find much on this topic, I hope I didn't miss the thread. Also I'm not sure if this is the right forum to put this thread in, if not I apologize and would appreciate a mod moving it to the correct spot.

Thanks!

 

[tjkj2002]

Well if you have the 42RLE ****** that is your problem,it has a very high reverse gear ratio of 2.1:1(almost all '03 KJ's and all '04+ KJ's).The '02 KJ and some early '03 KJ's came with the 45RFE ****** which has a 3:1 reverse gear ratio.

 

[flair1111]

Mine does this also. i had a flash done on it last summer and it seemed to help for awhile but it still does it. the flash seemed to take out some of the jerkyness, but its still weak as crap. the first time i ever noticed this was last summer i was showing my wife this insanely steep sub division i was having to survey. i went down one of the drives only to find i had about a 10X10' area to turn around in without dropping off a 50' bank on all sides.

i pulled the nose of the jeep about 3 feet from the edge and tried to reverse my way back...nothing! i tried 4 wheel...nothing! i had to get my wife to dig out from the front tires and still push it to 5500rpms just to get the dang thing to even try and budge. finally i had to wiggle it around on the edge of nothingness and backed out of the drive with the thing floored at 5k plus rpm and still almost didnt make it.


talk about being pissed off! i now avoid nose end first situations which is just sad and pathetic when driving a jeep.


i really think jeep should do a switch for the old trannys if an owner wants one free of charge. i almost lost my jeep that day and my life.

 

[Neal]

you have to use lo range to back up an incline

 

[tjkj2002]

I'll post this info again......................

NV1500-5 speed manual
-1st-3.96:1
-2nd-2.37:1
-3rd-1.49:1
-4th-1:1
-5th-0.83:1
-R-3.54:1

NSG370 6 speed manual
-1st-4.46:1
-2nd-2.61:1
-3rd-1.72:1
-4th-1.25:1
-5th-1:1
-6th-0.84:1
-R-4.06:1

45RFE 4 speed auto ******
-1st-3:1
-2nd-1.67:1
-2nd prime-1.50:1
-3rd-1:1
-4th-0.75:1
-R-3:1

545RFE 5 speed auto ******
-1st-3:1
-2nd-1.67:1
-2nd prime-1.50:1
-3rd-1:1
-4th-0.75:1
-5th-0.67:1
-R-3:1

42RLE 4 speed auto ******
-1st-2.84:1
-2nd-1.57:1
-3rd-1:1
-4th-0.67:1
-R-2.1:1

 

[J-Thompson]

there is a fix for it or at least a way to help it out
regear to 4.10
other wise deal with it

I know that is easy to say when you have the 45RFE and can spin 245/75 MTR,s on dry pavement in reverse but it is what it is

I deal with the fact that we wanted a TJ with an auto and I would only have the tried and true TF999 which is a 3 speed auto so when we get on I-10 we are pushing 3K to do 70 but hey I deal with it

 

[Marlon_JB2]

(almost all '03 KJ's and all '04+ KJ's)

While you're correct on all '04s+ having the 42RLE, I'd say from experience that most '03s have the 45RFE. Approximately only 3-4 months of '03s have the 42RLE vs. 7 or so months with the 45RFE.

But back to the issue at hand...

Normal. As previously mentioned, a transmission computer flash helps but doesn't eliminate the problem. This has been brought up before and something was mentioned about fluid not being pumped to the right area of the transmission, so it bucks when reversing up a hill.

 

[tjkj2002]

While you're correct on all '04s+ having the 42RLE, I'd say from experience that most '03s have the 45RFE. Approximately only 3-4 months of '03s have the 42RLE vs. 7 or so months with the 45RFE.

I've only known about 2-3 poeple that have the 45RFE in a '03,the other 100 or so all have the 42RLE,if I remember right the switch happened about 2-3 month's into the '03 production year.

 

[JeepJeepster]

Well if you have the 42RLE ****** that is your problem,it has a very high reverse gear ratio of 2.1:1(almost all '03 KJ's and all '04+ KJ's).The '02 KJ and some early '03 KJ's came with the 45RFE ****** which has a 3:1 reverse gear ratio.

Yup, theres your problem.

Ive never had trouble backing over anything(small cars in the mall parking lot are included) when in 4low. If you find yourself in a hole trying to back up just pop it into 4low, dont heat the ****** up.. Speaking of heating up the ******, you should also use 4low when youre crawling at low speeds so the already weak 42rle doesnt heat up. Ive never had mine overheat.

Never use part-time 4x4 or 4low on hard surfaces.

 

[leadfoot]

Yup, theres your problem.

Ive never had trouble backing over anything(small cars in the mall parking lot are included) when in 4low. If you find yourself in a hole trying to back up just pop it into 4low, dont heat the ****** up.. Speaking of heating up the ******, you should also use 4low when youre crawling at low speeds so the already weak 42rle doesnt heat up. Ive never had mine overheat.

Never use part-time 4x4 or 4low on hard surfaces.

Hi, and greetings from Australia!

This is my first post on this very informative forum.
To begin with I have very little experience with 4x4 vehicles(my personal taste in cars is closer to the Pontiac G8 which we export to your country, but with Pontiac being closed down I don't know what will happen) but the reason I am here is that my brother has just purchased a V6 KJ Cherokee Limited (I think you call them a Liberty?). It was manufactured April 04(42RLE auto) and has travelled only 25,000
genuine miles(40,000km-we are metric here in Aussie). Overall, he loves it, except for the fuel consumption of course.

Q 1. Since buying the Jeep, we have noticed the problem with reversing. A search led me to this thread but am a bit confused by the quote above.

"If you find yourself....just pop into 4low, don't heat the
****** up. Never use part time 4x4 or 4low on hard surfaces."

My brother's house has a steep driveway which is concrete. Is there any chance of damage to the transmission using this method. The driveway is 50 feet long. If it was my car I would "suck it & see", but it's his so I want to be careful as I am the family's car expert & don't want to end up with egg on my face.

Q 2. Can anyone explain why such a tall reverse gear was used in the 42RLE

Q 3. What is the final drive ratio in high and low range(or what is the
"underdrive" ratio in low.

Q 4. I have seen reference made to a "flash". What is it, and how do you do it on a 42RLE.

Q 5. At 25,000 miles, is it a good time to change the fluid? ****** operates fine except for the reverse problem.

Thanks for your help. I hope Chrysler(and GM for that matter) survive.

Kind Regards,
John.

 

[belvedere]

Q 5. At 25,000 miles, is it a good time to change the fluid? ****** operates fine except for the reverse problem.

Personally, I'd wait another 25k miles. ATF+4 is a high quality grp III fluid. I don't agree with Chrysler's "lifetime fluid" recommendation, but I wouldn't change it yet.

 

[Rednroll]

I've only known about 2-3 poeple that have the 45RFE in a '03,the other 100 or so all have the 42RLE,if I remember right the switch happened about 2-3 month's into the '03 production year.

Do you know what the easiest way is to tell if you have the 45RFE or not? I have an '03 and I have never noticed this problem with mine. Hearing all this talk about the differences has me curious now.

 

[HoosierJeeper]

Do you know what the easiest way is to tell if you have the 45RFE or not? I have an '03 and I have never noticed this problem with mine. Hearing all this talk about the differences has me curious now.

Check the sticker in the door jamb for date of manufacturing...

 

[leadfoot]

Thanks Belvedere.
Can anyone else help with the answers to my questions?

Regards,
John.

 

[J-Thompson]

&%#)#@!*&%^^&!!!!!!!

I didn't ask about what type of ****** I have. If that was my question I would have gone to this thread http://www.jeepkj.com/forum/showthread.php?t=33141.

Would it be possible to please stick to my original questions(except for Belvedere, of course, thanks)?

Regards,
John.

you have the 42rle
it has a tall reverse gear
there is NO way to "fix" a tall reverse gear in a trans
the only way to "fix" the issue of "no power" in reverse
is to lower the final drive gear ,which is 3.73 now, to 4.10
this would lower all gears
They used this high reverse gear for reasons unknown
A "flash" will not change the gearing so dont waste your time on that

4wd low range in every KJ that has a factory installed T-case is 2.72 to 1
You SHOULD NOT use 4wd low range or 4wd part time ,high range
on dry ground ,while I have never busted any thing with my Detroit locking both rear wheels every time I push the gas
and have wheeled where the traction was the same as on the street
while in 4 low with the ARB locked up front and a Detroit in the rear
most highly advise against it

I change the fluid in our KJ at 36K miles

 

[leadfoot]

you have the 42rle
it has a tall reverse gear
there is NO way to "fix" a tall reverse gear in a trans
the only way to "fix" the issue of "no power" in reverse
is to lower the final drive gear ,which is 3.73 now, to 4.10
this would lower all gears
They used this high reverse gear for reasons unknown
A "flash" will not change the gearing so dont waste your time on that

4wd low range in every KJ that has a factory installed T-case is 2.72 to 1
You SHOULD NOT use 4wd low range or 4wd part time ,high range
on dry ground ,while I have never busted any thing with my Detroit locking both rear wheels every time I push the gas
and have wheeled where the traction was the same as on the street
while in 4 low with the ARB locked up front and a Detroit in the rear
most highly advise against it

I change the fluid in our KJ at 36K miles

Now I have 2 conflicting opinions, the one quoted above and that given previously by JeepJeepster. Assuming that 4x4 Low cant be used at all on sealed surfaces will reverse gear eventually destroy itself unless I use the
services of a tow vehicle every time I need to reverse up a moderate incline?

Thanks,
John.

 

[Rednroll]

Check the sticker in the door jamb for date of manufacturing...

Mine says "9-02"....So I'm guessing that would be pretty early in the 2003 Model year build. So I probably have the 45RFE?

So now you know one more person with the 45RFE.

 

[HoosierJeeper]

Mine says "9-02"....So I'm guessing that would be pretty early in the 2003 Model year build. So I probably have the 45RFE?

So now you know one more person with the 45RFE.

To confirm it, get a build sheet from Jeep...it'll say.

 

[tjkj2002]

To confirm it, get a build sheet from Jeep...it'll say.

Build sheets have been notoriously wrong.Crawl under your KJ and visually check,I believe 13 bolts and it's a 45RFE and 15 is a 42RLE,but there should be a sticker on the drivers side if you have the 45RFE and it will say "RFE" on that sticker if you have the 45RFE.

 

[HoosierJeeper]

Build sheets have been notoriously wrong.Crawl under your KJ and visually check,I believe 13 bolts and it's a 45RFE and 15 is a 42RLE,but there should be a sticker on the drivers side if you have the 45RFE and it will say "RFE" on that sticker if you have the 45RFE.

Maybe I got lucky....but my build sheet seems accurate...