Just purchased my SRT-10 Ram BUT the speedo 9-10MPH off at highway speeds

Discussion in 'General Discussion' started by SRT10FOUR, Apr 7, 2020.

Car Parts
  1. SRT10FOUR

    SRT10FOUR New Member

    Messages:
    28
    Likes Received:
    18
    Joined:
    Apr 6, 2020
    Hey all! I just purchased my first SRT-10 Ram (2005 QC). I am having an issue similar to what our fellow user experienced here: https://www.vtcoa.com/threads/speedometer-is-off.68872/#post-1316828

    My circumstances seem to be almost the same as his, as I purchased the truck with stock rims and the stock tire size according to my build sheet. I saw that people have recommended asking dodge to perform some kind of service on the computer, but can someone tell me exactly what to ask for please?

    The reason I ask is because I purchased the truck from a Dodge dealer with several vipers and SRT vehicles on the lot, and when I brought this up on the test drive and after the pre-purchase inspection report I had done, they said they did not know how to fix it. They brought up their "Viper Mechanic" to speak to me and he just threw his hands up and looked at me like I was crazy for even asking/caring.

    I got an SCT tuner from Torrie, but he said that a tuner cannot fix this issue (and installed one of his tunes, which indeed did not fix the issue), so I am curious if anyone knows exactly what I can ask a different Dodge dealer to do for me?

    Other details: build sheet shows 305/40/22" tires, I just purchased 305/45's but have not had them installed yet. I did the math and the new rev's per mile would be 633.84. The speedo is off a lot more than the other user here, mine is off 10MPH at 75MPH and seems to be off by +1MPH every 10MPH after that.

    Thanks for any help in advance, guys! I'm pretty excited to start driving it once this whole pandemic is over.
     
    Kiwi SRT10 likes this.
  2. rottenronnie

    rottenronnie Well-Known Member Supporting Member

    Messages:
    3,160
    Likes Received:
    447
    Joined:
    Jul 4, 2006
    Location:
    Calgary, Alberta
    It seems your speedo is off by 16%, (HIGH, I'm assuming if you are looking at a taller rear tire to slow it down).

    You would have to first change your ecu back to stock with your controller (from Torrie), take it to a dealer and ask them to recalibrate (slow it down) your speedo by 16% and when you are done, you can reinstall your Torrie tune.

    That should solve your speedometer issue without affecting changes Torrie has made.

    If you have a Quad-Cab, that 1"+ tire height increase using a 305/45 may affect the operation of the ABS enough to confuse your automatic.

    It would be best to phone around and find a dealer that can recalibrate your speedometer. It takes a few seconds for them to do it. In the old days, there was a colour-coded worm-gear that was swapped out at the transmission end of the speedometer cable. The dealers have a chart for different tires sizes/gear ratios to determine what change to make.

    Modifications often scare guys at dealerships so drive in with the stock tune, have them plug into your OBD II port (same place you use for your controller when swapping tunes), make the change to the speedo and that's it.
     
    Kiwi SRT10, oldcolt and SRT10FOUR like this.
  3. beastmode1

    beastmode1 Full Access Member

    Messages:
    318
    Likes Received:
    61
    Joined:
    Oct 2, 2014
    Location:
    Denver, CO
    Welcome to the RBC. Hope your problems get addressed so you can enjoy the 10.
     
  4. beastmode1

    beastmode1 Full Access Member

    Messages:
    318
    Likes Received:
    61
    Joined:
    Oct 2, 2014
    Location:
    Denver, CO
    Rotten ronnie seems to have this problem figured out I would follow his lead on this one he's knowledge about the 10's is incredible.
     
  5. SRT10FOUR

    SRT10FOUR New Member

    Messages:
    28
    Likes Received:
    18
    Joined:
    Apr 6, 2020
    Thank you kindly! These forums are how I learned about Torrie, so we’re off to a great start.

    I’ve got some fun things I’m working on while I’m stuck at home the next few months, and hopefully I’ll get to share some pics in the new member section soon!
     
    AMS3 likes this.
  6. beastmode1

    beastmode1 Full Access Member

    Messages:
    318
    Likes Received:
    61
    Joined:
    Oct 2, 2014
    Location:
    Denver, CO
    Remember it costs money to go fast lol!!!!!
     
    Kiwi SRT10 and AMS3 like this.
  7. beastmode1

    beastmode1 Full Access Member

    Messages:
    318
    Likes Received:
    61
    Joined:
    Oct 2, 2014
    Location:
    Denver, CO
    FYI you should find a good mopar mechanic to help you with your 10 as it gets very pricey with the dealers. For the most part you should be able to do the repairs yourself if you are handy and that is when a good side mechanic comes in handy. There is a ton of knowledgeable people on our site who are eager to help like rottenronnie he has a whale of knowledge. Also look on ebay for things like oil filters etc and always use a Viper oil filter when changing your oil. The viper motor is very expensive. For the oil I use mobil 1 0-W40 recommended by dodge and i buy it at Walmart 2 5gallon jugs. It is cheaper there. Let us know if you need any other help.
     
    Kiwi SRT10 likes this.
  8. rottenronnie

    rottenronnie Well-Known Member Supporting Member

    Messages:
    3,160
    Likes Received:
    447
    Joined:
    Jul 4, 2006
    Location:
    Calgary, Alberta
    BTW Tuners can not compensate for front-to-rear height differences as the ABS data is hard-coded into the ECU to prevent tampering.

    My Tuner tried using somewhat of a back-door approach, and did manage to change it (in the wrong direction) which made the situation worse.

    I was too focused on raising the overall diameter in the back (to match the front 22") then Old Colt suggested why not go with 20s on the front and a proper tire to match the O/D of the rear. DOH!!

    That's what I did, problem solved.

    Now when I race those pesky Trackhawks, I don't have to worry about losing the race because my auto jumped into Overdrive Lockup just after 1/2 track because of the height mismatch between front and rear. :)
     
    Kiwi SRT10 likes this.
  9. oldcolt

    oldcolt Striker Heads and Cam Supporting Member

    Messages:
    2,689
    Likes Received:
    27
    Joined:
    Jul 14, 2008
    Location:
    Calgary, AB
    So I rescued you from a back-door situation, eh? lol
     
    Kiwi SRT10 likes this.
  10. rottenronnie

    rottenronnie Well-Known Member Supporting Member

    Messages:
    3,160
    Likes Received:
    447
    Joined:
    Jul 4, 2006
    Location:
    Calgary, Alberta
    I can't go for that.
    NoooooOh
    No Can Do!
     
  11. SRT10FOUR

    SRT10FOUR New Member

    Messages:
    28
    Likes Received:
    18
    Joined:
    Apr 6, 2020
    Nice! I'm trying to avoid heading to the store as much as possible, is this the same one? https://www.amazon.com/Mobil-120760...&keywords=mobil+1+0-W40&qid=1586353692&sr=8-2

    All of the Mobil 1 0-W40 on there seems to have "European" either on the top of the quart or in small writing under the weight ¯\_(ツ)_/¯ like this one that comes out to be more expensive per quart: https://www.amazon.com/Mobil-96989-...&keywords=mobil+1+0-W40&qid=1586353692&sr=8-4

    That one above was the cheapest one, but there is also this one: https://www.amazon.com/Mobil1-12387...&keywords=mobil+1+0-W40&qid=1586353692&sr=8-7
     
  12. AMS3

    AMS3 Active Member

    Messages:
    282
    Likes Received:
    95
    Joined:
    Aug 8, 2019
    Location:
    Savannah Ga
    Here is what I use: https://www.amsoil.com/lookup/auto-...8-3l-10-cyl-engine-code-h-e/?volume=us-volume
     
  13. SRT10FOUR

    SRT10FOUR New Member

    Messages:
    28
    Likes Received:
    18
    Joined:
    Apr 6, 2020
  14. rottenronnie

    rottenronnie Well-Known Member Supporting Member

    Messages:
    3,160
    Likes Received:
    447
    Joined:
    Jul 4, 2006
    Location:
    Calgary, Alberta
    8.7 U.S. quarts is plenty.

    There was some misinformation in the 2006 (?) owners' manuals to use more than that, but don't.
    Overfilling will overload the crank-scraper and the engine's will burn oil.

    The pans are all the same capacity 2004-2006 Gen III SRT-10 RAM.
     
    SRT10FOUR likes this.
  15. Pamooney3

    Pamooney3 New Member

    Messages:
    8
    Likes Received:
    4
    Joined:
    Mar 5, 2016
    Location:
    Kodak TN
    I spoke with dodge a few years back about the mobil1 0w40 what I found out was dodge and mobil1 had a falling out and dodge went with penzoil 0w40 instead. Look at the bottles they are formulated for our engines
     
  16. SRT10FOUR

    SRT10FOUR New Member

    Messages:
    28
    Likes Received:
    18
    Joined:
    Apr 6, 2020
    Ended up going with the Mobil 1 0W40 for my first oil change. I’ll see what it looks like a few months from now, although I won’t be able to put any real miles on the truck since I’m working from home for the foreseeable future.
     
  17. rottenronnie

    rottenronnie Well-Known Member Supporting Member

    Messages:
    3,160
    Likes Received:
    447
    Joined:
    Jul 4, 2006
    Location:
    Calgary, Alberta
    More info about oil under General Discussion (this site).

    Search for:

    Mobile One European Car Formula W0-40 oil
     
  18. Kiwi SRT10

    Kiwi SRT10 Active Member Supporting Member

    Messages:
    344
    Likes Received:
    222
    Joined:
    Dec 16, 2019
    Location:
    New Zealand
    Welcome aboard. Have fun Learn Heaps Make your Great Truck even better!!!
    That's what I am doing:)
     
  19. SRT10FOUR

    SRT10FOUR New Member

    Messages:
    28
    Likes Received:
    18
    Joined:
    Apr 6, 2020
    Sweet, that is the one we used :cool:


    Now if anyone needs the stock exhaust (that I'm told sounds like a UPS truck) from my 05 Quad Cab, please let me know or else the shop is going to toss it in the trash asap.
     
  20. beastmode1

    beastmode1 Full Access Member

    Messages:
    318
    Likes Received:
    61
    Joined:
    Oct 2, 2014
    Location:
    Denver, CO
    I have run Mobil One 0-W40 since I have owned the 10 No worries at all and believe me it Purrs like a kitten but do not let the Ford, chevy wannabes underestimate the 10 lol!!!!