Q: My jeep has a 2.5 4cyl. 35 in. tires and 4.56 gears. At full speed it only reaches 60 to 65 m.p.h., in fourth gear, it is only turning around 3500 r.p.m.'s if I go to fifth it looses speed. Why is that all I can get on top speed. I have changed fuel filter, and checked fuel pressure. What could be wrong?
A: Assuming that the catalytic convertor is not plugged, the rolling resistence of the too tall tires times the 1 to 1 ratio of the 4th gear is more than the power of the engine can overcome......... Ed
Drive Train / Driveline Upgrade Not applicable Not applicable
Q: There are two Aisin-Warner manual trans used in jeeps: the ax 5 and the ax 15. The ax 15 is reputedly superior to the ax 5. The ax 15 was used in 6 cyl wranglers, comanche and cherokees from 1989-97, including the new TJ series wranglers with four cylinder engines. My question is can the ax 15 be used in lieu of the ax 5 (provided in stock 4 cyl YJ wranglers) with minimum modifications- if required at all?
I believe that both are very similar with 10 spline input shafts and bolt up to the np 231 transfer case. I am unsure about input shaft diameter, length, and trans to bellhousing bolt pattern, bellhousing clutch line access, and related clutch details.
I've just had my stock ax 5 rebuilt with all new bearings, synchronizers, seals, and it continues to refuse to downshift from 4th to 3rd without grinding until reaching very low speeds (under 10 mph). All clutch componets were replaced new, as was the pilot bearing. There is no other problem and all gears upshift smooth as silk, but downshifting from 4th to 3rd has ground since i bought the car and continues to do so even though the trans was rebuilt. Thus, I am looking to upgrade to a superior trans- the ax 15. Any insight would be appreciated.
A: The Ax 15 is a better transmission and I believe is not a difficult upgrade. Have you test driven a Jeep with this transmission in it to make sure it downshifts smoothly? Ed
Q: I have just tuned my carburetor and the idle sticks at a high rpm. There is a pin that is attached to a part that is attached to the carb that is preventing the whole assembly from returning to it's original position and therefore keeping the rpm's up. It sticks sometimes.
A: There should be an idle screw that controlled the idle speed. Check it, and lower the idle speed by srewing the screw in!
Q: leaks oil neer the oil pan, had oil pan gasket replaced, rear seal replaced, and cannot find out where the leak is occurring. It is coming from the right side of the engine, dripps down along the bellhousing of the transmition, and near front where gas line goes under oil pan.
A: It's leaking from the engine block where the oil line connects to the engine!