klparker Report post Posted January 4, 2016 Have a 2001 Itasca Horizon, @75,000 miles, and having trouble getting over hills (even small ones) without a toad. Have push button Allison transmission, diagnostic code is oL-70, Sump fluid temp too low. However, when code was checked the coach had been driven for several hours. No warning lights on transmission or engine and manual check of transmission fluid was OK. The coach shutters/vibrates and rpms and power drop when going up hills; runs fine on level roads. Can you help us get over the hills, please. Parkers 2001 Itasca Horizon Toad, 2006 Pontiac G-6 Share this post Link to post Share on other sites
wolfe10 Report post Posted January 4, 2016 Most likely suspect is clogged fuel filter(s). Absolutely the place to start with your symptoms. Climbing grades requires the most fuel. If fuel flow is restricted, this is where the "clogged filter(s)" issue will show up. Do you have one or two fuel filters? If two, does the secondary fuel filter base have a manual primer pump? BTW, that is not a diagnostic code on the Allison, just an oil level check. To get to diagnostic codes: Key on, engine off, push the up and down arrows on the Allison shift pad. This takes you to the oil level check (where you got the oL-70 code). PUSH THE UP AND DOWN ARROWS AGAIN. This brings you to the diagnostic codes. It will be d-1, followed by the code. If no code, it will be d-1 followed by - -. If there is a code, after recording it, push the mode button to go to d-2. Push D or just turn off the key to exit. Share this post Link to post Share on other sites
klparker Report post Posted January 4, 2016 No addtl. codes on transmission. Have two fuel filters, however, don't know if there is a manual primer pump. Will check and get back. Thanks for providing us somewhere to start checking. Parkers Share this post Link to post Share on other sites
wolfe10 Report post Posted January 4, 2016 The manual primer pump will be on the secondary fuel filter housing. If no pump, there will be a block-off plate held in place by two bolts. Remove the plate and you can install the manual primer pump if you do not have one. The manual primer pump makes filter replacement a lot easier and less messy! This is what the manual primer pump looks like: https://parts.cat.com/en/catcorp/105-2508-105-2508-product More information on fitting a secondary fuel filter and PN's for the manual pump: http://forum.dieselrvclub.org/index.php/topic,6611.0.html Share this post Link to post Share on other sites
klparker Report post Posted January 8, 2016 Changing the filters was correct. Thank you so much for all you help and advice. Safe & Happy Travels, The Parkers Share this post Link to post Share on other sites
