2005 LJ overdrive issues

geoff@2469

geoff@2469

New Member
Joined
May 31, 2019
Messages
4
Location
Missouri
About 2 weeks ago I picked up a salvaged 05 LJ (it was a theft). Since then I have had a new waterpump put on it and the cooling system flushed. It drives wonderfully as long as it doesn't get into O/D. Once it shifts into 4th gear, the CEL comes on, and when it down shifts goes into limp mode. the code is p1776. I went and had the solenoid changed out and fluid and filter changed (mech said it looked good). When we got it, the o/d kickdown switch was gone, so I have ordered another one and am waiting on it. Is it ok to just drive in 3rd? and if so what are the max rpms I need to look for?
 
  • Like
Reactions: Wranglerfix
Yes, by all means it is 100% okay to drive in third gear.

The sweet spot for the 4.0 is between 2-3k RPMs, so as long as you're cruising in those RPMs, you're just fine.

However, even if you exceed those RPMs, you'll also be just fine. Sure, I wouldn't drive 200 miles at 5k RPM, but I doubt you're stupid enough to do that ;)
 
  • Like
Reactions: Wranglerfix and geoff@2469
Yeah, That would probably not be a good idea. Thanks for the response. This is the first Jeep we have owned and from reading forums, there is ALOT of info to learn about.

01A9D6CA-CA40-4BE8-B9AF-0D0D8D577175.jpeg


C16A3F26-488F-426A-982D-97A52ABD8857.jpeg
 
  • Like
Reactions: Wranglerfix, skrelnik and MountaineerTom
geoff@2469 said:
About 2 weeks ago I picked up a salvaged 05 LJ (it was a theft). Since then I have had a new waterpump put on it and the cooling system flushed. It drives wonderfully as long as it doesn't get into O/D. Once it shifts into 4th gear, the CEL comes on, and when it down shifts goes into limp mode. the code is p1776. I went and had the solenoid changed out and fluid and filter changed (mech said it looked good). When we got it, the o/d kickdown switch was gone, so I have ordered another one and am waiting on it. Is it ok to just drive in 3rd? and if so what are the max rpms I need to look for?
Click to expand...
Hey did you ever fix this I am having a similar issue.
 
  • Like
Reactions: Wranglerfix
I'm no electrical, computer or transmission whiz. The o/d button gone bugs me...watch for weird stuff...like pinched wires, etc. I had a harness get hot once and did similar stuff, and rats eat one in a car.
 
  • Like
Reactions: Wranglerfix
@Crasse My first instinct is wiring...Was the overdrive issue occurring with your old
Pcm?

You can send it back in and I will test it in my Jeep if you would like.
 
Wranglerfix said:
@Crasse My first instinct is wiring...Was the overdrive issue occurring with your old
Pcm?

You can send it back in and I will test it in my Jeep if you would like.
Click to expand...
It did happen a couple of times prior to the new computer. I will check some of the wiring first and see if I can find something. If I can’t I will send you an email. Thank you @Wranglerfix
 
  • Like
Reactions: Wranglerfix
Hey guys update on this one. So I didn’t have anything that looked funny with the electrical components so I decided to get under the Jeep and open the pan up. While I was under there I decided to change the filter, replace the oil ( roughly 4 quarts) and clean the pan. Ialso re-torqued the valve body. After this was performed I didn’t have any other issue so far. My only concern is when I checked my trans dip stick a few days later I did notice it still had a slightly dirty color to it. I’d assume it is because replace the filter and oil in the pan is roughly a third of the oil. My question is would it be a bad idea to flush the system and if it isn’t a bad Idea. Should I be changing that filter again after a flush? Thanks guys and sorry to be a pest I just want to make sure this transmission last a long as possible being it is my daily/weekend warrior.
 
I’ll give you a heads up that 4 qts is the absolute minimum you should add after draining the pan. I understand that the FSM states 4 qts but I’ve always had 5 qts drain from the pan and 5.5 qts when I also replace the filter.

It’s been my practice to drain the pan (I have a drain plug) then add 5 qts and run the engine for 45 seconds then drain and refill again.

A flush wouldn’t be a bad idea but I’ve always used the above method and my 42RLE still works at 251,000 miles.
 
  • Like
Reactions: Rubicon John
AjRagno said:
I’ll give you a heads up that 4 qts is the absolute minimum you should add after draining the pan. I understand that the FSM states 4 qts but I’ve always had 5 qts drain from the pan and 5.5 qts when I also replace the filter.

It’s been my practice to drain the pan (I have a drain plug) then add 5 qts and run the engine for 45 seconds then drain and refill again.

A flush wouldn’t be a bad idea but I’ve always used the above method and my 42RLE still works at 251,000 miles.
Click to expand...
Oh sweet where did you get the drain plug from?
 
Top Bottom
Back