46RE Delayed Engagement: Causes, Pressure Tests and the Fix

A 46RE that sits in Drive for two or three seconds before the truck creeps, or that thumps into Reverse long after you moved the lever, is not filling a clutch fast enough. That is all delayed engagement is. Either line pressure is slow to reach the apply piston, or it gets there and leaks away. The hard part is working out which, because Chrysler's own diagnosis chart for the 46RE lists thirteen causes for this one complaint, from a dipstick check to pulling the pump.

This guide covers the 46RE behind the 5.2L and 5.9L gas engines in Ram, Durango and Dakota. Factory numbers come from the 2001 Ram (BR/BE) service manual, including the pressure test analysis chart that tells you which circuit is leaking. The valve body side comes from Sonnax and from Bob Warnke's cooler flow article in Transmission Digest. Sources are listed at the end.

Recommended 46RE parts for delayed engagement

A replacement pump for worn gears or a scored bushing, a Sonnax-updated valve body for worn regulator and manual valve bores, and a master kit for the seal rings and clutch seals. Secure checkout.

46RE Pump 1994-2003

$230.98View part

46RE Valve Body 2000-2001 - Sonnax Updated, Dyno-Tested

$525.00View part

46RE Master Rebuild Kit 1998-2002

$307.98View part

What Has to Happen When You Pull It Into Gear

The shift lever moves the manual valve, which opens line pressure to the apply circuit the range needs. Nothing moves until that piston strokes.

• Drive, first gear: the rear clutch applies and the overrunning clutch holds. The rear clutch is the forward clutch. If it is slow to fill, the truck is slow to move forward.
• Reverse: the front clutch applies and the rear (low-reverse) band holds the low-reverse drum through the rear servo.
• Both ranges: the overdrive unit's direct clutch is spring-applied in first through third, so it carries torque in both Drive and Reverse without needing oil.

Every circuit shares one pump, one pressure regulator valve, and the seal rings on the reaction shaft support and input shaft. The converter and cooler hang off the same regulator. So the first question is always: slow into Drive, slow into Reverse, or both?

The Factory List of Thirteen Causes

The 46RE diagnosis chart in the 2001 Ram service manual (pages 21-492 and 21-493) lists these causes under "Delayed Engagement (From Neutral to Drive or Reverse)":

1. Fluid level low
2. Filter clogged
3. Gearshift linkage misadjusted
4. Torque converter drainback (oil drains from the converter into the sump)
5. Rear band misadjusted
6. Valve body filter plugged
7. Oil pump gears worn or damaged
8. Governor circuit and solenoid valve electrical fault
9. Hydraulic pressure incorrect
10. Reaction shaft seal rings worn or broken
11. Rear clutch/input shaft and rear clutch seal rings damaged
12. Regulator valve stuck
13. Cooler plugged

Two corrections are worth reading twice. For drainback: if the vehicle moves normally within 5 seconds of the shift, no repair is necessary; if longer, inspect the pump bushing and replace the pump. For a plugged cooler: a transfer case failure can plug the cooler. On a 4x4 with a transfer case history, check that first.

The 5-Second Rule and Why the 46RE Drains Down

The classic complaint is the first start of the day: a few seconds of nothing, then fine all day. That is the converter emptying into the pan overnight. The pump has to refill it before full pressure reaches the clutch.

Chrysler fitted a check valve to fight this. Per the service manual (page 21-606), the converter drainback valve sits in the cooler outlet (pressure) line near the radiator tank, a spring-loaded check ball that opens at about 2 psi (the same spec appears in the 1998 Ram service manual). It is serviced only as an assembly, never cleaned. It must come out whenever the cooler is reverse flushed, and installed backwards or in the wrong line it blocks flow and overheats the transmission. If a previous shop left it out after a flush, the morning delay is often the first sign.

Sonnax's "The Cure for the Common (Chrysler RWD) Cold" explains why the RE family is prone to this. The OE manual valve does not charge the converter in Park, so the fill only starts after you pull the lever into gear. The same article warns about an old shop trick: drilling a line-to-lube hole to fix lube starvation. It helps lube flow, but gives the converter one more path to drain when the engine is off. If you find that hole drilled, plug it before installing any fix.

Sort the Complaint Before You Test

Slow into both Drive and Reverse, worst after sitting

Drainback. Check the drainback valve and its orientation, then the pump bushing and converter hub. The factory procedure (page 21-491) says replace a scored pump bushing, and polish a scored converter hub with crocus cloth or replace the converter.

Slow into both, all the time

Low line pressure or a starved pump: fluid, filters, pump gears, a stuck regulator valve or a cooler restriction. The tests below separate these.

Slow into Drive only

The rear clutch circuit: its oil crosses the reaction shaft support and input shaft seal rings before reaching the piston. Chrysler lists a burnt rear clutch and worn input shaft seal rings under "No Drive Range (Reverse OK)," and a long Drive-only delay is often the early stage of that.

Slow into Reverse only

The front clutch and the rear band. A loose band makes the servo take up slack before it grabs, so adjust it first. Our 46RE no reverse guide covers the front clutch and rear servo checks.

Step 1: The Checks That Cost Nothing

• Fluid level and condition. Mopar ATF+4, type 9602, checked hot. Low fluid lets the pump pull air. If the pan is full of clutch material or metal, the factory chart says an overhaul is needed. Our 46RE fluid guide has the capacity and check procedure.
• Pan filter. A clogged filter starves the pump in every range.
• Gearshift linkage. If the case lever is not squarely in its detent, the manual valve only half opens the circuit. The manual's preliminary diagnosis says to adjust throttle and gearshift linkage on any delayed, erratic or harsh shift complaint.
• Rear band, if the delay is in Reverse. Pan off. Loosen the locknut 5-6 turns, tighten the adjusting screw to 72 in-lb, back it off 2 turns, then hold it and torque the locknut to 25 ft-lb. Pan bolts go back at 13 ft-lb (service manual page 21-540).
• Codes. The chart lists a governor circuit and solenoid valve electrical fault, with a scan tool test as the correction. Pull codes before you put a gauge on it.

Step 2: The Pump Volume Check

The service manual has a quick flow test most people skip (pages 21-554 and 21-555). With the fluid level correct, disconnect the To cooler line at the cooler inlet into a container and idle in Neutral. One quart in 20 seconds or less is acceptable, the same limit Chrysler printed in the 1998 Ram service manual. Intermittent flow, or longer than 20 seconds, sends you to the pressure tests. Never collect more than one quart, or you risk internal damage.

Good flow means the pump is making volume and the converter circuit is open. Weak flow points at the pump, filter, regulator valve or a converter circuit restriction.

Step 3: Put Gauges on It

The factory tests use a 100 psi gauge (C-3292) on the accumulator port and a 300 psi gauge (C-3293-SP) on the servo ports, rear wheels free on a hoist, cables disconnected from the valve body levers (pages 21-488 and 21-489). Two matter most here:

• Test One, manual low at 1000 rpm: line pressure 54-60 psi with the throttle lever forward, rising to 90-96 psi as it moves rearward. Rear servo pressure within 3 psi of line.
• Test Four, Reverse at 1600 rpm: rear servo port 145-175 psi with the lever forward, rising to 230-280 psi.

These same Test One and Test Four ranges are printed in the 46/47RE pressure test procedure of Chrysler's 1998 Ram Truck service manual, pages 21-217 and 21-218 [2], so the specs hold across the RE family from the late 1990s on.

The service manual's pressure test analysis chart (page 21-490) turns those readings into a location. The entries that matter for a delay:

• Line pressure OK in R but low in D, 2 and 1: leakage in the rear clutch area, meaning seal rings or clutch seals.
• Pressure OK in 1 and 2 but low in D3 and R: leakage in the front clutch area.
• Pressure OK in 2 but low in R and 1: leakage in the rear servo.
• Pressure low in all positions: clogged filter, stuck regulator valve, worn or faulty pump, or low oil level.
• Lubrication pressure low at all throttle positions: clogged cooler or lines, leaking seal rings, worn pump bushings, pump, clutch retainer or a clogged filter.
• Line pressure OK during any one test: the pump and regulator valve are OK.

That last line is the one people miss. If pressure is right in any one test, the pump and regulator are fine, and a one-range delay is a leak in that range's circuit. Correct pressure that is slow to come up after the shift is the converter and cooler refilling first: drainback or a restriction.

Step 4: Rule Out the Cooler Circuit

Bob Warnke's Transmission Digest article on 46-47RH/RE cooler and converter flow lists delayed engagement and slow converter fill among cooler-flow complaints, and calls cooler restriction "by far the most-common issue": the drainback fitting, an auxiliary cooler, the radiator cooler or the lines. Back pressure pushes the switch valve toward its spring, where its spools stage mid-circuit and choke flow further, becoming a problem as head pressure nears 80 psi.

His test: bypass the cooler circuit and retest. If the delay goes away, find the restriction, starting with the drainback valve. Our 46RE overheating guide covers cooler flow testing.

Step 5: The Valve Body Fixes

The factory correction for a stuck regulator valve is just "clean," which works only if the bore is healthy. Sonnax's 46RE/47RE vacuum test guide ties the 4-spool manual valve to delayed engagement and the switch valve to no cooler flow in Park and converter bushing failure. Our 46RE valve body testing guide covers the bench test.

Three Sonnax parts address the engagement complaint directly:

• Manual valve 22771-09. Sonnax: the OE manual valve design does not allow converter or cooler charge in Park. Their valve charges the converter in Park, so the fill is done before you shift, without dragging the forward clutch.
• Lube-regulated pressure regulator valve 22771A-02K. Feeds the converter charge circuit as soon as the engine starts, and its internal check stops drainback through the orifice with the engine off. Sonnax recommends pairing it with the manual valve.
• Line pressure plug and sleeve kit 22229-01K. A worn plug and sleeve causes poor Forward and Reverse engagement and poor cooler charge at idle. The 01K kit fits the .200 in. plug; 22229-04K fits the .264 in. plug.

Check one thing before you order: Sonnax's fitment rule for its PR and manual valves is to look at the OE pressure regulator valve. If the spools on the inboard end get progressively smaller, like a Christmas tree, their valves fit. If the end spools are all the same diameter, do not use either one in that valve body.

Step 6: When It Is Internal

If the pressure test points at the rear clutch area or the front clutch area and the valve body checks out, the leak is inside, and the transmission has to come out. The chart's corrections for items 10 and 11 are to remove the pump and replace the reaction shaft seal rings, or disassemble the unit and repair the rear clutch, input shaft and seal rings.

While the pump is out, check it against the factory numbers (pages 21-556 and 21-557): inner and outer gear clearance to the reaction shaft housing of 0.0004 to 0.0025 in. each, measured with Plastigage. Replace the pump or support if the ring grooves or machined faces are scored or pitted. On a delay complaint the seal rings are why you are in there, so replace them.

Set clutch clearances on reassembly: 0.025-0.036 in. for the rear clutch and 0.070-0.129 in. for the front clutch (page 21-532). A loose rear pack takes longer to stroke, which feels like a Drive delay even with good pressure. Our 46RE rebuild wear points post covers the other hard parts.

Frequently Asked Questions

How long is too long for a 46RE to engage?

Chrysler's own rule in the 46RE diagnosis chart is 5 seconds. If the truck moves normally within 5 seconds of shifting into gear, no repair is needed. If it takes longer, the factory correction is to inspect the pump bushing for wear and replace the pump, after the cheaper checks like fluid level, filter and linkage are ruled out.

Why does my 46RE take a few seconds to go into gear in the morning?

The torque converter drains into the pan overnight, and the pump has to refill it before the clutch gets full pressure. A missing or failed drainback check valve in the cooler pressure line, a worn pump bushing, or a drilled line-to-lube hole in the valve body all make it worse. The OE manual valve also does not charge the converter in Park, so the fill only starts when you pull the lever into gear.

Can low fluid cause delayed engagement on a 46RE?

Yes. Low fluid is the first cause on Chrysler's delayed engagement chart. The pump pulls air along with fluid, and the apply circuit fills slowly. Check the level hot with ATF+4 type 9602 before doing anything else.

What pressure should a 46RE have in Reverse?

In the factory Test Four, with a 300 psi gauge on the rear servo port and the engine at 1600 rpm, Reverse pressure should be 145-175 psi with the throttle lever forward and rise to 230-280 psi as the lever is moved rearward. Low Reverse pressure with good pressure in 2 points at the front clutch area or rear servo, depending on which other ranges are also low.