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Repair Questions and Answers.

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 #394946  by Nick82
Hello all

My transmission has a leak and I’ve been putting in a quart of fluid every 2 to 3 days. Haven’t had the time to try to actually fix it. Today I was driving and it went in to limp mode, which has been an issue since I got the car, but usually I can put it in park, shut it off, restart it and it’s fine. Today it wouldn’t come out of limp mode and then I saw my speedometer isn’t working.

Any ideas?
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 #394947  by M-Pressive
You need to figure out why it is dumping fluid.

You may have run it low enough that it damaged something.
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 #394948  by EasyRider300M
If the speedometer wasnt indicating your speed and tranny went into limp mode, then most likely it's a bad transmission output sensor. Replace output sensor on exterior of transmission (a very easy replacement) and that issue may be resolved. But get that leak diagnosed and fixed asap.

There is a detailed step by step description with pictures on how to change the output sensor in our Knowledgebase forum. You have to be a paid member to access it. Lots of other repairs that may be needed on our Ms are in the Knowledgebase. Membership is just $15 for the first year and $10 for each additional year. It is best investment you can make in maintaining your M. I've been a paid member for over 20 years.
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 #394961  by Nick82
Yeah I thought the speed sensor could be the culprit. Planning on buying one and replacing it this weekend, which leads me to my next question…. It seems like every parts store has 2 of each brand that will both fit my vehicle and one is about $10 more than the other. For instance they list a duralast for $30 and then another duralast for $20 and both fit my vehicle… what is the difference between the two?

And yes I know I need to figure out the leak and fix it asap. Just have very little time and money to work on the car. And yes I know I’m spending more in the long run on fluid than what the repair would probably cost but it’s easier to come up with $12 every few days than an unknown higher amount all at once. And I depend on this vehicle to get back and forth to work so can’t just wait and save money. Rock and a hard place situation…
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 #394962  by Nick82
Also thanks for the advice!

The car has a few other costly issues, so I’m not sure how much longer I’ll have her, but what I would like to do is keep her as a project car to fix up when I do have the time and money. I’ve had it about 6 years now and we’ve been through a lot together lol. Lots of blood, sweat and tears put into keeping this thing going over the years, and this forum has been a huge lifesaver many times in the past. I’ll shamefully admit I was a lurker, searching for a problem I was having and looking through old posts for the info. Recently I made an account so I could ask a question from the amazing people here. If I end up keeping the car I will definitely get a paid membership to help myself out with more detailed stuff, and to give something back to the place that has helped me so much
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 #394963  by Nick82
Ok just realized one is an input and one is an output. And you already told me I need output. :lol:
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 #394964  by EasyRider300M
The output sensor is easier to replace than the input sensor. It's rearward on the transmission on the outer edge if my memory serves me right. There are pictures and a description of replacement in the Knowledgebase.
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 #394969  by EasyRider300M
If you become a paying member, here's what you can access in the Knowledgebase part of the forum. Lots of repair step by step procedures. Well worth the price of admission.

0: Lubrication & Maintenance
Fluids, Capacities & Towing
Moderator: Moderators 6 Topics
31 Posts Approved transmission oils fo…
by tafi300M
Sat Jul 18, 2015 11:14 am
2: Suspension
Front, Rear & Alignment
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181 Posts Re: HOW TO: Restore your Susp…
by In-trepid
Sun Oct 23, 2022 7:24 pm
3: Driveline
Half shafts, aka Driveshafts
Moderator: Moderators 6 Topics
32 Posts Re: If you notice play in tra…
Mon Mar 07, 2022 7:10 pm
5: Brakes
Front, Rear, Parking, Hydraulics & ABS
Moderator: Moderators 16 Topics
205 Posts Re: How To: Front and Rear Br…
by Cypressdelight
Thu Mar 08, 2018 6:16 am
7: Cooling Systems
Engine, Transmission, Drive Belts, Radiator & Thermostat
Moderator: Moderators 24 Topics
215 Posts Re: Water Pump Information, L…
Fri Jan 26, 2024 1:16 pm
8A: Audio
Radio, Amplifier, Antenna, Steering Wheel Switches & Speakers
Moderator: Moderators 15 Topics
87 Posts Re: A Better Understanding of…
Mon Dec 05, 2022 1:15 pm
8B: Chimes & Buzzers
Moderator: Moderators 0 Topics
0 Posts No posts
8C: Clock
Moderator: Moderators 1 Topics
11 Posts Re: HOW TO: Remove the Clock …
by Brando26
Thu Mar 13, 2014 9:50 pm
8E: Electronic Control Modules
Including SKIM, BCM, PCM, Seats & Mirrors
Moderator: Moderators 2 Topics
7 Posts Re: REFERENCE: PCM/ECM inform…
by Mopar1
Tue Jun 01, 2021 8:46 pm
8F: Engine Systems
Electrical, Battery, Starting, Alternator & Charging
Moderator: Moderators 8 Topics
158 Posts Big 3 Upgrade
by M-Pressive
Tue Jan 23, 2018 8:49 am
8G: Heated Systems
Glass, Mirrors & Seats
Moderator: Moderators 2 Topics
12 Posts Re: How-To: Repair Seat Heate…
Mon Sep 04, 2017 8:40 pm
8H: Horn
Moderator: Moderators 0 Topics
0 Posts No posts
8I: Ignition Control
Operation, ASD Relay, Cam Sensor, Coils, Knock Sensor & Plugs
Moderator: Moderators 8 Topics
84 Posts Re: HOW TO: Replace Cam Senso…
by allella
Wed Feb 15, 2023 10:52 am
8J: Instrument Cluster
Moderator: Moderators 7 Topics
42 Posts Re: Cluster Replacement
by mrnrod
Wed May 10, 2023 7:26 am
8L: Lamps & Lighting
Exterior, Interior & Switches
Moderator: Moderators 25 Topics
358 Posts Re: Best bulbs for 01 Lbs Hea…
Tue Jan 16, 2024 6:04 pm
8M: Message Systems
Moderator: Moderators 0 Topics
0 Posts No posts
8N: Power Systems
Locks, Mirrors, Seats & Windows
Moderator: Moderators 8 Topics
56 Posts Re: Window Switch Repair/Chro…
Mon Sep 05, 2022 12:13 pm
8O: Restraints
Seat Belts, Air Bags & Clock Spring
Moderator: Moderators 2 Topics
14 Posts Re: Clockspring Replacement
by Bill Putney
Fri Feb 21, 2014 12:40 pm
8P: Speed Control & Cruise Control
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0 Posts No posts
8Q: Vehicle Theft Security
SKIM & Transponder Key
Moderator: Moderators 5 Topics
42 Posts Re: Turning off horn when loc…
by AndyPre
Sun Jan 26, 2020 4:55 pm
8R: Wipers & Washers
Moderator: Moderators 1 Topics
9 Posts Re: How To: Change wiper motor
by Floater
Mon Aug 27, 2012 3:22 pm
8W: Wiring
Including Diagrams, Pin Outs, Fuses & Power Distribution
Moderator: Moderators 4 Topics
8 Posts Positive Battery Cable & Fusi…
by mrnrod
Tue Aug 01, 2023 6:31 pm
9: Engine Mechanical
Including Timing Belt & Water Pump
Moderator: Moderators 23 Topics
304 Posts Re: HOW TO: Change Timing Bel…
by allella
Wed Feb 22, 2023 4:05 pm
11: Exhaust System
Including Catalytic Converters & Mufflers
Moderator: Moderators 1 Topics
7 Posts Re: REFERENCE: Detailed Dual …
by Basslicks
Wed Oct 19, 2016 4:02 pm
13: Frame, Bumpers Covers, Fascia & Cradle
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13 Posts Re: HOW TO: Fix Bumper After …
by Wolfe359_01
Fri Mar 10, 2017 5:13 pm
14: Fuel System Delivery
Injection Tank, Pump, Injectors, TPS & Fuel System Sensors
Moderator: Moderators 9 Topics
66 Posts Re: HOW TO: Remove the Thrott…
Fri Feb 12, 2016 3:33 pm
19: Steering
Column, Rack, Tie Rods & Pump
Moderator: Moderators 5 Topics
71 Posts Re: HOW TO: Inner Tie Rod Bus…
by 2001_blue_300m
Mon Mar 23, 2015 9:37 pm
21: Transaxle
All Transmission, Final Drive, Speed Sensors & Shift Cable
Moderator: Moderators 15 Topics
218 Posts Re: DTC P0700 AND P1776 - 30…
Tue Nov 21, 2023 11:07 am
22: Tires & Wheels
Including TPM
Moderator: Moderators 10 Topics
75 Posts Re: Snow Tire Size Question?
Sat May 14, 2022 7:59 am
23A: Body Exterior
Includes All Panels, Latches, Grills & Mirrors
Moderator: Moderators 13 Topics
124 Posts Body Aperture Panels Image
Tue Dec 19, 2023 12:49 pm
23B: Body Interior
Includes Seats, Instrument Panel, Sun Roof & Weather Stripping
Moderator: Moderators 20 Topics
162 Posts Finger Tip Interior Door Pull
Mon Oct 02, 2023 5:23 pm
24: Heating & Air Conditioning
ATC & Evaporator
Moderator: Moderators 15 Topics
176 Posts Re: HOW TO: Replacing the bl…
by ggariepy
Fri Oct 30, 2020 8:57 pm
25: Emissions Controls
Moderator: Moderators 7 Topics
95 Posts Re: NVLD System Test/Repair C…
Thu Jan 25, 2024 1:48 pm
Paint Codes
Moderator: Moderators 1 Topics
11 Posts Re: REFERENCE: Paint Codes an…
by tafi300M
Sun Sep 11, 2016 5:22 am
Interior Color Codes
Moderator: Moderators 1 Topics
15 Posts Re: REFERENCE: 99-04 Interior…
by Tim_ettinger
Thu Mar 02, 2017 10:42 am
Part Number Reference
Moderator: Moderators 10 Topics
119 Posts Re: REFERENCE: 300M Part Numb…
by Bill Putney
Mon Nov 11, 2013 7:31 pm
Moderator: Moderators 6 Topics
72 Posts Re: An indispensable tool: Ca…
by TrueBlue
Tue Jul 29, 2014 9:57 am
Media Reference
PDF's, DTC Code Listings
 #395145  by Nick82
Ok so I changed the output sensor and it worked for a day then the next day when I started it the speedometer started going up and down while I was in park, then stopped working and went into limp mode again. Should I try changing the input sensor too or is it an electrical issue? Bad wiring? Bad sensor? Computer? Also can’t figure out where it’s leaking tranny fluid. Don’t see any leaks anywhere… anyone have any ideas?
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 #395148  by FIREM
1)Common fluid loss is from transmission cooler and or lines. Especially where the hard lines connect to rubber line.
2) Chrysler sensors in general need to be replaced with genuine OEM Mopar parts. Aftermarket tend to not last or work well. ( example OEM Cam sensor will pick up 7grams, aftermarket only 3grams. Poor magnesium from new)
3) Speedo “wagging” when not moving is typical of electronic noise. Most commonly caused by poor grounding. Disassemble and clean every ground connection. Lastly have the alternator tested, on car, for excessive ripple.
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 #395152  by In-trepid
FIREM wrote: March 3rd, 2024, 7:46 am
2) Chrysler sensors in general need to be replaced with genuine OEM Mopar parts. Aftermarket tend to not last or work well. (example OEM Cam sensor will pick up 7grams, aftermarket only 3grams. Poor magnesium from new)
Bob, can you explain 7 grams vs 3 grams? What is being measured? Having a background in electronics and hall effect sensors, I have never heard the term of grams when measuring this type of sensor.
User avatar
 #395155  by FIREM
Large paperclips are 1 gram each by weight.
Mopar sensor picked up 7 consistently, aftermarket 3. More sensitive than measuring ounces.
May not be a scientific formula however is an observable fact.
Magnetic strength directly related to sensor signal strength and gap for Hall Effect or MPU.
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 #395156  by In-trepid
Thanks Bob. I now understand the rationale in grams.
 #395180  by Nick82
Thanks I’ll look into these potential solutions. Really appreciate it!